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How to just about survive in Android OS

If purchasing hardware, beware of “Shanzhai” models: these typically break down after 3 to 4 months, and some reportedly shipped with malware (e.g. Tecno). Reputable manufacturers’ devices should last several years, although some ‘budget’ options have been known to last less than two. Devices advertised as “waterproof” are not necessarily *usable* in wet weather, and can have overly-sensitive touchscreens even in dry weather.

Regarding BlackBerry devices, I believe the situation is:

Before Blackberry 10 - No Android support

Blackberry 10 (Q10, Passport etc) not upgraded to 10.2 - Simple, non-NDK applications can be repackaged for BlackBerry

10.2.1 - APKs install direct to phone; NDK works; most APIs supported, except for things like taking over the home screen or running a background sound recorder when app is not visible

Priv - *is* Android (a “security-enhanced” fork of Android 6 through 9, all of which are no longer supported)

but I haven’t actually tested any BlackBerry device; in particular,

I don’t know if their physical keyboards are large enough to justify their higher prices,
and I don’t know to what extent the 2022 shutdown of their OTA provisioning service has affected the reliability of calling etc on Blackberry 10.

Some pre-4.4 devices, such as the Galaxy S2, are advertised as having 16G capacity, but only 2G of this is “device memory” and the rest appears as a fake “USB disk” which not all applications can use for their data.

The “Application Manager” can be told to move some applications to the “SD card” (actually the fake USB disk), and may be able to move more applications if you first connect a cable and do adb -d shell pm set-install-location 2, but moving an application does not usually result in all its *data* being moved—many applications still keep a lot of data on the more limited “device memory” even when the *code* is elsewhere.
On the Galaxy S2, some “device memory” can also be freed by dialling *#9900# for SysDump and selecting “Delete dumpstate/logcat” (repeat every few months).
Some of these devices can be repartitioned to turn part of the “USB disk” into “device memory” (using, for example, a GNU/Linux box running Heimdall and an appropriate PIT file for the Galaxy), but you’d then need to re-flash the operating system from a download: many are of questionable legitimacy, and it also risks a USB glitch ‘bricking’ the device, so I cannot recommend this procedure.

Newer devices are less likely to come with such inconvenient partitions in their memory.

Real MicroSD cards (usually SDHC i.e. up to 32GB) are supported by some (not all) devices, and can be used for storage of media but not all applications before Android 6 (which can “adopt” a card for extra “internal” storage instead), but any new card must be tested with f3write and f3read (or equivalent) before use, since counterfeit high-capacity cards are common (e.g. “32G” where only 7.4GiB work reliably, even if the seller describes it as “genuine” or “authorized”). Many counterfeit sellers, when faced with a test report mentioning h2testw (a proprietary Windows equivalent of F3) issue a refund and tell you to keep the card. Such cards are often usable if repartitioned downwards to their true (smaller) capacity

on GNU/Linux the easiest way to do this is probably to install gparted;
on a Mac:

1. in the Terminal, check with mount to see which disk number it has,

2. unmount it with diskutil umount

3. use (e.g.) fdisk -e /dev/disk1 (ignore any “could not open MBR file” errors)

4. edit 1 and set true size in 512-byte blocks

5. w and q—Disk Utility will likely pop up (launch it yourself if it doesn’t)

6. select the first partition e.g. disk1s1 (*not* the partition table itself!) and erase.

Usual disclaimers apply of course: mistakes with partitioning can erase your hard disk; if in doubt, leave it to an expert.

but repartitioned cards probably *shouldn’t* be used for Android 6+ internal storage until somebody checks that setup honours the altered partition table.

If you don’t have time for all this testing, complaining, repartitioning, and repeating until you get a high enough capacity, it’s well worth paying the extra few pounds to buy from a reputable high-street chain instead of online (but test it anyway, just in case they too get caught out).

You might also want to find an A1 or A2 logo to check the card is fast during random (not just sequential) access, depending on how you plan to use it.

Android 4 has a “Font size” setting under “Display” (although the range is limited); Android 6+ has “Accessibility” settings including Font size and also “Display size” which changes the reported DPI—this can work better with some applications. Also available is the “TalkBack” screen reader, and a built-in screen magnifier—a bug in Android 13 can make its scrolling lag by dozens of seconds and sometimes lock so the phone needs soft-resetting; this seems to have been fixed in Android 14.

Taming the Home screen

Some devices ship with ‘widget’ software that plays a continuous stream of advertisements from the Home screen, consuming your data allowance and generally being a distraction—especially if you intend to use your device to demonstrate things to others. Sony’s “What’s New” is one such example and cannot be disabled from Settings/Apps. I was initially able to mitigate this by using Sony’s “Simple Home” (which can give larger print, although the customisation options for Version 1.0 on Android 4.x don’t allow for removal of its three “speed dial” slots—I suggested moving these to the top i.e. furthest from your hands if you don’t make voice calls from this device), and I suggested refusing to accept OS updates (such as from 4.4 to 5.0) just in case the update removes Simple Home and brings back the “What’s New” widget (Android security is basically a lost battle anyway—even Google’s own “Nexus” models have ceased to be patched just 3 years after initial release—so you should be aware that anything you store is at risk of compromise no matter what; if the consequences of that are worse than inconvenience, keep it on something that’s more secure than Android)—but it turns out there’s a way to turn off pre-installed widgets without relying on the availability of Simple Home. The instructions that should have been in the box are as follows:

Unwanted widgets etc can be long-pressed and then dragged to a dustbin which appears (except on the “Amazon Fire” version of Android, where you may be stuck with them but you can at least change the order or drop them on top of each other to hide them in folders);
on Android 4.x and 11.x a ‘pinch’ gesture can be used to remove empty ‘panes’ (pages) if you’d rather have just a single page (automatic on 5–10)
If the device will be used by a beginner who’s unfamiliar with the difference between short and long presses, I suggest not placing tappable icons anywhere near where the dustbin or “create folder” functions appear when they are long pressed;
The print size *might* be increaseable in Settings but not by much; doing so will likely reset the layout to default; Simple Home (if available) might be preferable.

In about 2024 some Android devices started shipping that don’t even display buttons for Home and Back (let alone have physical ones like the early models)—on these you might have to swipe from the bottom to reach the Home screen (or if you prefer see if there’s a Dock setting under System / System Navigation or similar, which might be useful if the “swipe from bottom” logic has crashed and you don’t yet want to restart the phone), or swipe and hold (or swipe while *on* Home) to reach the running applications list, and swipe from the left to go Back or to minimise the keyboard.

Useful applications

Unless otherwise specified, these can be searched for in the “Play Store”, but beware that advertisers can pay for other apps to be listed at the top of the search results, so the app you searched for is not always the first result.

Hacker’s Keyboard: The only application I could find with a correctly laid out on-screen Dvorak keyboard, although it’s still not as good as a physical keyboard (which is sorely lacking from most Android devices). Hacker’s Keyboard is Apache-licensed.
QKSMS by Moez Bhatti (Android 5+; if not listed by Play Store for recent devices, you can try F-Droid’s APK): If your phone shipped with a messaging app that insists on sending long SMS messages as premium MMS “picture” messages, you might prefer to install this app which does not. It’s open-source, tested with TalkBack and has a night mode. It’s also able to send Unicode messages by default, unlike some preinstalled messaging apps that require this to be turned on in a setting misleadingly named “input mode” (actually transmission mode)
If you’re stuck on Android 4.1 to 4.4 (which cannot run QKSMS) and need to send long messages, then your only option is probably an old version of Textra (its version 4.3 supported Android 4.1, and 4.5 supported Android 4.4) or ChompSMS (version 8.34 for Android 4.1, 8.55 for Android 4.4).
920 Text Editor (on Android 8 or below; APKs on GitHub, no longer on “Play Store”): a small GPLd text editor that also tends to appear at the top of Simple Home’s application list. Does not run on Android 9: try TwoSevenTwo’s “I<code> Go” Code Editor (larger) instead [this was removed from Play Store in July 2020], or use the editor bundled with Speed Software Explorer but that one has smaller fonts, is more complex to start and has no syntax highlighting. Text editors are always useful: even if you won’t be editing, you might at some point need it for converting the clipboard contents to text (so it can be pasted into an application that does not do so itself) or to save something to a file, and 920 can also double as a rudimentary file manager if you don’t have one. It’s not Emacs though: its syntax highlighting is limited and it’s slow with large files. Beware it can crash (for example, at least some versions crash when a Bluetooth keyboard is connected or in low-memory situations), so text that has not been saved is highly vulnerable.
Speed Software Explorer: A file manager. If your device shipped with a non-advertising version of File Commander which later updated to one that advertises, or if you were annoyed when ES File Explorer started to promote festive “themes” on its Home screen and gambling games on its Apps screen, then you might prefer this one which was still without advertisements last time I checked. Can also create shortcuts to specific files on the Home screen, provided that Simple Home is not running at the time of shortcut creation. (Android 5+ can use Google’s “Files Go”, which usually ships with Android 8+ by default, but you might still want Speed Software Explorer if Files Go is insufficient.) Explorer can read the “Android/data” directories of other apps in Android 4 through 10 but this was blocked in Android 11 (and their workaround didn’t work for me on an Android 12 device and the blocking got stronger on Android 13) so you might need the bundled Files app for this.
VLC (also on iOS): GPL’d media player with speed control and playlist navigation which is often lacking on manufacturers’ preinstalled players. (iOS version also has video-download functionality not present in iOS’s browser.) You might however wish to keep the old player installed as well, because MIDI files are not yet supported by all versions of VLC. VLC became Android 4.2+ in April 2019; older versions are still available for 4.1 etc.
AntennaPod: MIT-licensed “podcast” (audio RSS) client with variable-speed playback etc: can simplify download for sites using that format for audio articles. (Version 2.5 increased the minimum Android requirement from 4.1 to 4.4.)
Recent versions of iOS have a built-in “Podcasts” app with similar functionality, but the “Podcasts” app in iOS 8 and below lacks the option to add your own URL
VX ConnectBot (no longer on Play Store) or JuiceSSH: VX is Apache-licensed and supports port forwarding (might be needed for desktop SSH), but not password remembering for servers that don’t “do” public-key authentication and its landscape mode might need manual configuration; Juice lacks these limitations but the unpaid version can’t port-forward, and Version 3 began to require Android 8—on earlier devices you’ll need an older APK. VX has a built-in file uploader but this doesn’t always work, and the scp command available on the local shell doesn’t work in all Android versions, but you could use ssh -C user@host 'cat > filename' < filename or ssh user@host 'tar -c directory | xz -9' > downloaded.txz
On Android 7+ (and *possibly* still working on 5 and 6 but I haven’t tested this), you might prefer Termux for its more complete local shell with installable packages (including SSH, expect etc)—pinch to zoom; pull out multisession options from left; Paste option appears on long-press menu once text is available; you can’t scroll during select so you must temporarily zoom out, and on smaller devices horizontal arrow keys require Hacker’s Keyboard to be set to 5-row
If you only have iOS, try Arnaud Mengus’s “WebSSH Essential” application (Arnaud was kind enough to add some larger fonts when I beta-tested).
Organic Maps (also on iOS 12+ for iPhone 6+ etc): A fork of Maps.Me offline maps without the advertisements.
In 2021 the package name was changed (and the old version is no longer supported by map-download servers); to update, you might have to back up your bookmarks, uninstall and reinstall.
Android 4 might instead need Axet Maps (no longer on Play Store); to avoid crashes use the old version 9.1.8 of upstream Maps.Me to download maps from June 2019 and the same version of Axet to use them (don’t update). On more recent Android please use Organic Maps to avoid problems with Axet.
I didn’t recommend the unmodified Maps.Me (also on iOS) because I saw it carry advertising for scam get-rich-quick schemes and gambling apps, although that no longer seems to be their business model in 2023: in February they turned off most advertising on Android 6+ (except hotels and the wallet service), in June they limited downloads to 10 maps with a “pro” subscription to lift the limit (similar to the less-responsive OsmAnd), and in August they added a Product Hub.
In places like Cambridge, OSM data tends to be better than Google data, e.g. for walking directions and building labels. But if you only need Google-level data, *their* Maps app now has “advanced options” to download areas of your choosing for offline use (with some exceptions e.g. mainland China), so you *could* just use that. (In 2020 they moved these options to the “Account” menu at top right.)
GPS Status & Toolbox (also on iOS; beware advertising): Provides (among other things) a way to force the phone to update its ephemeris data to give faster GPS fixes for a few days. Useful because some design flaw made Android’s automatic GPS management often insufficient and there’s no way to force it in the system’s own settings; older Android devices can become noticeably slow at acquiring GPS (if they manage to at all) without this utility. Third-party advertising was added to the unpaid version at the end of December 2017; the last version not to have it was 8.0.168. Then in April 2021 version 11 increased the minimum Android requirement to 8, so you’ll likely need to side-load an older version for older devices.
GPS Status & Toolbox can also read other sensors (Menu > Diagnose sensors), the most useful of which is the light-intensity sensor (in lux) which can help you check lamps for phosphor degradation. The ‘step counter’ is less useful as it counts only when activated (and is reset on boot).
Google PDF Viewer (no longer on Play Store): Does not require you to zoom out before turning pages as some bundled viewers do. Scrolls vertically; default zoom is page width. If you prefer horizontal scrolling with default zoom to full page, try MuPDF (AGPL, no longer on Play Store) which also reads EPUB etc. On Android 6+ you might prefer Adobe Acrobat Reader 21+ which has Liquid Mode (tries to reflow documents in big print, but doesn’t always work) and a speech-synthesis button
Google Docs: Can view Microsoft Word files offline (and tends to be faster and a bit smaller than Microsoft’s own app, unless that one came preinstalled on your device). Some ‘chat’ apps (e.g. WeChat) *require* a .doc viewer to be installed before you can access any .doc file a contact might send you—there is no option to save the file for later viewing on another device.
Lithium EPUB Reader (Android 4.1+): Comparatively low resource requirements, night-theme option, font zooming (up to a point) and remembers your position when reloaded. Closed-source but without advertisements last time I checked. Can have trouble with wide tables (Annogen-generated apps like “Pinyin Web Browser” handle EPUBs with wide tables, but don’t duplicate Lithium’s other features like popup footnotes).
CHM Reader X (newer versions are Android 11+): Useful if you sometimes need to consult offline documentation in CHM format; this reader is faster than others when dealing with large files. Closed-source but without advertisements last time I checked. When dealing with framesets, you can show only one frame by editing Android/data/com.pdagate.chmreader/files/chmReaderState and changing page: (see text strings near start of chm file to figure out what to set it to), then bookmarking the result. Then use this bookmark whenever you need to go back to the within-frame starting page (as the reader defaults to opening the last page visited).
kWS (no longer on Play Store): Simple Web server suitable for sharing files over WiFi, which can be useful if Bluetooth is too slow or not working. You’ll need to switch on “hotspot” functionality (disable mobile data first if you don’t want clients using up your quota); the IP and port that clients should browse to is displayed on kWS startup. Some older devices (e.g. WM6) might not be able to connect to the hotspot, even in Open mode, due to subtle protocol changes over the years. Some applications have their own WiFi-sharing functionality but that usually requires the same application to be installed on all devices; a Web server requires only a browser.
Fractoid (Dave Byrne, no longer on Play Store): GPL’d fractal viewer, in case you ever need to explain the concept (but don’t expect it to be as fast as XaoS on a desktop)
EUMLab Pro Metronome (also on iOS): Useful for musicians if someone asks about tempo during a rehearsal and nobody has brought a metronome. This one is currently without advertisements but is closed source. Subdivisions require a paid upgrade.
K-9 Mail: Apache-licensed fork of the Android 4.4 email client with fewer problems (in particular, deleted messages are less likely to reappear on sync just because their flags are different on the server); has dark theme and configurable font sizes (may require restart), and a default folder can be set (useful when working with ImapFix). Old version 5.6 or below is required for Android 4.x; OAuth 2 (now used by some “cloud” email providers) has ‘wobbly’ support in version 6.2, or you might be able to set an “app password” (or on Android 5+ try “FairEmail” which can do OAuth2 to GMail and also set default folders etc)
Web Widget by Dennis Kempf (no longer on Play Store): No longer maintained but still just about works on Android 10 if you want to display arbitrary information on the Home screen and are not running SimpleHome: works best when pointed at your own server so you can fully control the appearance from the server side, but beware it hard-codes a short timeout (so if writing a CGI make sure it’s fast even if widget updates are mostly non-interactive); it can refresh more frequently than asked and frequently clear its display due to timeout anyway. And on Samsung phones it can set off spurious “background power drain” alerts (but if “put to sleep” it stops updating completely even when tapped)
Alternatively on Android 6+ (5+ in pre-2023 versions) “KWGT Kustom [sic] Widget Maker” can create a widget to fetch and display a piece of text, without markup, but without the timeout and load issues. Use the wg command, set Items / Text / Type = Fixed Width, use a combination of that width value (which sets margins) and Layer / Scale (which sets size), and set touch action to Disabled (or to launch an app of your choice) if you don’t want a single tap to bring you back to the edit screen.
Beware of CamScanner Phone PDF Creator: Commercial software whose full version used to be available without charge via some universities (and became popular at Cambridge), but the developers have since been dangerously careless, resulting in remotely-controlled malware infections on both iOS and Android (and also the promotion of gambling). The fact that this happened *multiple* times caused me to feel the developers haven’t learned and are likely to do it again. If you *must* use CamScanner, I suggest obtaining an APK for the old version 4.3.0 (2016-12-01), use it without registration (as it’s no longer supported by their servers), and, if possible, crop off the watermark on your scanned PDFs before showing them to others so as to avoid promoting a dangerous app. But there are alternatives:
Android 7+ can run “Microsoft Office Lens—PDF Scanner” and recent versions of this can process scans and create PDFs offline (the old Android 6 version requires a server which is probably no longer supplied, but you can use imagemagick’s convert command to concatenate them and create a PDF,
and the “Google Drive” app (which is often bundled by default) has a “Scan” option that can do both the image-processing *and* the PDF-assembly offline (even on Android 4.x), although of course it will also insist on uploading the PDF to its “Drive” server as soon as there is a data connection.

You might like to try both and see which one’s image-processing works best with your documents.

Contacts Backup Ultimate (SpecSoft, no longer on Play Store): Useful if any of the device’s Contacts have higher-resolution (720x720) images: the standard Contacts application reduces their quality on export (at least up to Android 10). But the non-standard XML plus PNG backup will not easily import into another device without this app or a conversion script. For VCF format on Android 5+ there is “Super Backup” from MobileIdea Studio but beware (a) it plays noisy video advertisements that can flash (epileptics might want to look away from the screen) and (b) Android does not *internally* store contact images as JPEG, so exporting to that format is *not* suitable for repeated operations—re-importing (perhaps after edits to the file) and re-exporting (after changes on the phone) will result in worse images than the first export, because the JPEG compression artefacts were converted back to bitmap and then re-encoded, so if you need repeated import-export then you’d better have your scripts take images from the earlier version when possible. (It may also be advisable to take any TEL lines with PREF in them and place them before other TEL lines in the same VCARD, as some phones fail to import this attribute and just set the default number to the first one listed.)
Samsung Internet: On phones (not tablets) running Android 5 and higher, recent versions of the Chrome web browser changed the tab switcher to a “grid” version that significantly reduces the size of page previews, which is bad for low-vision accessibility. The ability to revert this using chrome://flags was disabled in Chrome 91 (May 2021), and Firefox’s settable tab grid is only slightly less small. If you don’t want to risk known-insecure older versions of Chrome, you could try Samsung Internet (its “tab stack” does reduce the previewable area but doesn’t shrink the font so much)—also has a universal dark-mode switch, and its option to change text size takes fewer taps to reach (which can be useful if some bad web design makes a site impossible to navigate unless you temporarily reduce size and struggle; Chrome, Firefox and Ecosia have size settings under Accessibility which takes a little longer to reach). Samsung Internet does sometimes have issues opening applications though and you might at least sometimes need to use Chrome. In new Chrome, at least tabs *within the same group* can be switched without preview by first scrolling up a little.
Seconds Clock Widget (no longer on Play Store): Android versions 4.2 to 4.4 can add widgets to the lock screen; this one shows a seconds count with the time, which is not normally done by default, and is useful if you need to start a conference or something at an exact time and the wall clock is too far away to see. On newer versions of Android you might be able to get the seconds by tapping the clock on the lock screen, but this can vary with manufacturer.
OS Monitor (Android 6 and older): GPL’d monitor of processes, network connections and logs: can be useful when diagnosing other applications with problems (can also look up the locations of servers they’re connecting to, etc)
Privacy Flashlight Lite (Android 4 and older, no longer on Play Store for the UK): No-nonsense torch (with ‘widget’) for devices that have a camera light. Android 5+ bundles this functionality.
WangQi’s “My Home Button” (no longer on Play Store): Useful on older devices with worn-out hardware home buttons. When I last checked, it sometimes had advertising on its Settings screen but mercifully not elsewhere.
Onall QR Code Scanner No Ads (Android 4.2+, not currently on Play Store): Reads QR codes with comparatively little ‘nonsense’. Android 9 and *some* Android 6+ devices bundle this functionality so won’t need this app. Android 4.0 and 4.1 devices won’t be able to run Onall’s app and might be stuck with the advertisement-funded “QR Code Reader” by “Sustainable App Developer” which lost its “No Ads” tag in November 2018—use a version earlier than 1.1.9 (2021) if on 4.0 (and if you have to side-load an old version anyway then you might want to try one earlier than the version 1.0.7 that introduced advertisements). This latter app also has a zoom function which makes it more suitable for scanning QR codes at a distance.

You might also wish to check:

1. Your local transport authority or bus company (if you are a bus user), for example Cambridgeshire’s “MyBusTrip” (annoyingly listed under M by Simple Home; this can be worked around by assigning it a place on the dial-pad) presents the same data as on the bus stop signs, which might be useful if your stop lacks a sign or you’re not close enough to see it; some buses are actually tracked while others are just assumed to be in their timetabled locations. See also nextbuses.mobi although I’m not sure if they always use the same data.

2. Your bank: they just might have an application that works better than their website (for some tasks), although few if any banks test on all versions of Android so don’t be surprised if they break it

3. Any large marketplace site you sometimes happen to use (again their application might work better than their website for some tasks, but might break on some versions of Android)

4. Any large supermarkets you sometimes use for deliveries (same applies)

5. Your local library (some of them subscribe to digital audiobook services)

6. Any other large organisation(s) you’re associated with might have applications to expedite access to their servers and/or reading material, which might be worth checking (especially if they allow offline use)

7. Any “chat” networks your contacts use (but beware of commercial licenses and data use)

Since at least Android 4.x, background data can be restricted per application in Settings (usually under Data Usage), and Android 9 finally implemented my suggestion of also allowing Wi-Fi connections to be limited—useful for connecting to “personal hotspots” etc.

“Wi-Fi Calling” on Android

“WiFi calling” (the ability to route voice calls, and sometimes SMS messages, to and from your mobile-phone provider via WiFi when the building you’re in blocks their signal) is not a “standard” feature of Android, but is provided as an extra by certain manufacturers on certain devices. Therefore there is no specific “minimum Android version” that supplies WiFi calling—you have to choose from one of these particular models: Galaxy S6+, HTC 10+, Huawei P10+, Nexus 5X+/Pixel+, Xperia XZ1, E&OE, but beware Huawei phones made after late May 2019 no longer use the Google application store due to American trade sanctions.

On some Android 9+ handsets (e.g. upgraded Galaxy S9), the option to enable Wi-Fi Calling is *hidden* until the mobile network sends the handset a secret code to ‘un-hide’ it. This is *different* from the general procedure of enabling Wi-Fi calling on your account, and not all call-centre employees understand the need to perform *both* operations—so it may take *multiple* calls to technical support to get this fixed. (For Vodafone UK, I found the “online chat” facility to be better at solving the problem than the call centre, but your mileage may vary.)
Even if your mobile network supports voice-calling over WiFi, it might not also support SMS over WiFi. But if you have *very weak* phone signal—just enough for messages but not enough for a voice call—then you can have both phone and WiFi switched on and the device should route traffic appropriately.
WiFi calling is not generally supported when you roam abroad (presumably because the system won’t ‘know’ which country-code to default to).

The old “inTouch” app from H3G UK ceased to be supported on 15th May 2019. This used to make WiFi-calling available on more devices (by carrying it separately from the phone’s built-in dialler) and was a reason to choose the Three network on such devices, but this is no longer the case.

Sound-recorder applications on Android OS

Students recording lectures etc have generally moved from dedicated hardware to mobile ‘apps’ (applications). Below are my notes comparing some of the available alternatives on the Android platform. Usual disclaimers apply.

I only list apps that:

1. Work in the background and/or with screen off (saving battery),

2. can record a long talk even in the unpaid version of the app.

Android 9 and above does not allow telephone calls to be recorded: any recording happening at the same time as a call will get silence for the duration of the call. Therefore if you plan to both record a talk and call somebody to listen live, you’ll need two separate devices (unless you’re running an older version or you managed to ‘root’ it).

StereoMatch “Amazing MP3 Recorder” (removed from “Play Store” in May 2024; APK at stereomatch.com)

Pros:

Works with screen readers
Large controls, easy to operate (problems with early versions have been fixed)
Visual indication of microphone pick-up on the left of the screen

Cons:

Closed source (although currently without advertisements apart from suggestions to upgrade to Pro)
If you don’t like reading about voice changers and what people do with them, you might not appreciate some of the “what’s new” updates (but there haven’t been so many of these recently)

If you record OGG (MP3 encoding is a paid add-on but OGG is provided), the default settings give about 72 kbps for speech (31M/hr, variable).

Onall Sound Recorder No Ads (removed from “Play Store” in March 2019)

Pros:

Unpaid version can record to MP3, which might be useful if you need to share the recording with someone who can’t play OGG and you can’t first recode it (although recoding might still be a good idea for speech, as when set to 44.1k it seems to approximate lame’s --abr 80 setting)
Decibel readout during recording (might be useful for making noise complaints?)

Cons:

Closed source
Small controls
Switching off the screen during recording results in the app being backgrounded, which makes pause/stop take longer later

Triveous Voice Recorder

Pros:

Visual indicator of microphone pick-up

Cons:

Closed source
Poor use of storage space. Although Triveous *can* compress to AAC (or M4A in version 5; 128 kbps = 55M/hr, convertible via mplayer -ao pcm:file=output.wav or some installations of Audacity), it *also* makes an uncompressed WAV of the current track while encoding, so you need to allow space for this and/or keep each track short,
and the old Version 3 even fails to delete them (for tracks exceeding about 18 minutes depending on hardware)—this was fixed in Version 4, but the device still needs space for the WAV of each track while recording that track, regardless of the “realtime” setting (non-realtime results in an extra encoding step taking about 50% of the recording time).
If you *do* have space for WAV (3.3hr/G) then for distant sources it’s (usually) better to *just* use WAV and re-code it later, but this is no longer an option in version 5 which is M4A-only (but *still* has the “need to leave room for the WAV as well” limitation that StereoMatch doesn’t have).
Triveous also requires Android 4.4 or above, so won’t work on old 4.1 phones like the Galaxy S2

Rehearsal Assistant (removed from “Play Store” in December 2017)

Pros:

Cons:

Serious bug when recording uncompressed (see its SourceForge Bug 4)—on some devices, if you do too much in other apps such as the browser, background recording can be aborted *without* clearing the red indicator on the notification bar, leaving an incomplete wav file that needs sox --ignore-length to play.
For nearby sounds you could try the 48 kbps AMR-NB .3gp (loadable in Audacity, mplayer etc) but the quality is lower.

iPhone ships with Voice Memos (possibly under Extras); this too works with the display switched off or in the background, and records 64kbit AAC (.m4a). Some other iOS programs output .aif files that might need converting on a Mac.

Legal

All material © Silas S. Brown unless otherwise stated. Acrobat is an Adobe trademark. Adobe is a trademark of Adobe Systems Incorporated in the United States and/or other countries. Android is a trademark of Google LLC. Apache is a registered trademark of The Apache Software Foundation. Bluetooth is a registered trademark held by the Bluetooth Special Interest Group. Firefox is a registered trademark of The Mozilla Foundation. GitHub is a trademark of GitHub Inc. Google is a trademark of Google LLC. H3G is a trademark of Hutchison Whampoa Enterprises Limited. HTC and Touch are trademarks of HTC Corporation. Huawei is a trademark of Huawei Technologies Co., Ltd registered in China and other countries. iPhone is a trademark of Apple in some countries. Linux is the registered trademark of Linus Torvalds in the U.S. and other countries. Mac is a trademark of Apple Inc. Microsoft is a registered trademark of Microsoft Corp. MP3 is a trademark that was registered in Europe to Hypermedia GmbH Webcasting but I was unable to confirm its current holder. QR Code is the UK registered trademark of Denso Corporation. Samsung is a registered trademark of Samsung. SourceForge is a trademark of VA Software Corporation. Unicode is a registered trademark of Unicode, Inc. in the United States and other countries. Vodafone is a trademark of Vodafone Group Plc. WeChat is a trademark of Tencent Holdings Limited. Wi-Fi is a trademark of the Wi-Fi Alliance. Windows is a registered trademark of Microsoft Corp. Xperia is a trademark of Sony Ericsson Mobile Communications AB. Any other trademarks I mentioned without realising are trademarks of their respective holders.