nokia2720

as i described in @/phones, i wanted a new non-smartphone. so i decided to get a nokia 2720 4g (2019) flipphone. i have a pic at @/phones.jpg that shows how it looks like in terms of size compared to my nokia 105 (2013) which was made obsolete by the 2g network shutdown in my area and pixel 4 that i used while i was waiting for the new phone. as you can see, it's bigger than my old phone. but that's still pretty much the smallest non-2g phone i found.

this phone runs kaios. kaios is a linux that runs some old version of firefox and all the apps on it are just html5 websites. it's a fork of firefox os and is optimized for phones with keypads.

and as expected, by the default it comes with lots of quirks that i needed quite some time to reconfigure. fortunately it's relatively easy to tweak the phone so at least that prevents one from getting unreasonably angry about the "design choices" its developers have made.

let me document the tweaks i needed to make. i'll try to be detailed so that if i ever need to switch to another kaios phone, i'll be able to set it up from scratch again.

there's a site called bananahackers. it's a collection of guides scraped from some kaios mailing list. it's a bit annoying site but it was very useful for me to figure out things.

there's quite a few hacks i did. some are straight from bananahackers, some are my own findings:

if you decide to go down this path then make sure you don't make a mistake. it's very easy to mess up the whole phone and turn it into a brick. i managed to make a mistake when editing the launcher's source and the phone's ui got completely broken. fortunately i could still start wallace-toolbox with gdeploy or webide so i could reenable root and push a fix. had i messed up the system app, then things would have been much harder.

note that all the patches below are against kaios 2.5.2. an upgrade would probably invalidate most of my hacks so i hope it won't come anytime soon. although you can easily turn the updates down if needed.

so let's start. i assume linux as your hacking device. the tools you need are: adb and kaiosrt. kaiosrt is basically just an old firefox that still has webide enabled. you would use that to sideload apps to the phone or to tweak some hidden settings. alternatively you can use gdeploy to sideload apps. i prefer the latter since you can easily run it from the command line. software sources:

enable debugging mode with "*#*#33284#*#*". a little bug icon should appear in the top status bar. now connect the phone to your computer via its usb cable. the device should appear when you run "adb devices".

use gdeploy to install the wallace-toolbox app. in that app you can enable call recording. i've enabled it because i have terrible hearing and would prefer to listen back to some conversations to ensure i picked up correctly everything. the conversations will appear in a callrecording folder on its internal storage. use mtp (e.g. mount it via go-mtpfs) to get to the folder when connected to it.

use wallace-toolbox to enable the developer menu. this unlocks a new option in the settings (settings->device->developer) where you can toggle the debug mode without needing to remember the code.

use wallace-toolbox to make all apps removable. then you can use the right soft key in the launcher to bring up the menu that will now contain an uninstall option for all apps. i only kept these:

that's 9 apps. it fits one screen without scrolling so that's nice. i think the rest is unneeded. just use an actual computer to do the rest of the stuff (e.g. browsing, gps, listening to recordings, radio, snake, etc).

use wallace-toolbox to enable adb root too. after that "adb shell" will log you in as root and you will be able to overwrite the builtin apps this way. you'll need to enable this after each reboot so maybe keep wallace-toolbox around or somehow make this autoenabled on boot.

there's one more easy setting you can do: disable the flip to answer. i often want to reject a call so that i can call back immediately. i'm on a company paid plan with unlimited calls so it's simply more cost effective for me to call back my wife. for that i need to open my phone, reject the call, and then call back. to set this up, start up kaiosrt and connect to the device. in it go to runtime -> device settings, find the option phone.answer.flipopen.enabled and set it to false. you might need to reboot. i've learned this one from the r/kaios subreddit.

all the system apps live at /system/b2g/webapps. in order to replace some of them, you need to copy the target app to /data/local/webapps and point the app's dir to the new path. to do that you need to edit /data/local/webapps/webapps.json and change the target app's basePath property to /data/local/webapps.

let's start with the disabling the startup sound tweak to demo all this. keep in mind that all the patches i show are against the formatted code. just use a js formatter to reformat the files and then they are easy to edit. i used clang-format with the google style but beware clang-format seems to mess up code where there's a missing semicolon at the end of the line. by messing up i mean the code won't work anymore. maybe apply the patches manually on the unformatted code directly.

a system.gaiamobile.org directory should appear in your current directory and it should contain a file called application.zip. it's best if you can edit the files right in the zip file so that you don't need to unzip/rezip the contents. modern distributions of vim can do this already but probably other modern editors too.

i just pretty much completely disable the startOsLogoSound function's body. after you made this change push this back to to the phone:

notice that this time we are pushing to /data/local/webapps. make sure to edit /data/local/webapps/webapps.json too:

there shouldn't be any startup sound. all changes below need a reboot in order for the phone to pick them up.

from now i'll just show the patches i used for the various tweaks. make sure to pull and push each of the change the same way as the system app.

this tweak is from the bananahackers site. basically if you want to type in a number while typing a message, you can long press a button to make it a number. but the duration is overly long so you can lower that like this:

i didn't find an option to use custom sounds for the alarm clock. it's entirely possible i just missed an option for this. but what i did is that i just replaced

i really hated the default selection. i dislike alarms that suddenly scare me awake. what i want is some white noise that gets louder slowly. i downloaded some 1 minute rain mp3 from some sound sharing site, opened it in audacity, applied a fade in effect over the whole sound, exported it to ogg, and then put it into the clock's application.zip. it worked just fine.

it baffles me that the "assistant button" is not configurable on this phone and it defaults to that useless google assistant thingie that i immediately deleted. a much better use for that button would be to toggle the flashlight.

however i don't want the pressing itself to be the flashlight toggle. i want to reserve that for checking the time. i want to hold the button for a little while to toggle it. i managed to set this up.

there is already some support in the code for holding down the button. that's what triggers the assistant. it needs a bit practice to get the hang of it though. i think that's because of the phone's deep sleep mode. the first time you press the button, the code can't seem to be able to successfully set up any timers or do any time related operations. so the first time you press the button, you basically turn the phone up. then the clock should now be visible on the external screen. only now try to hold the button to toggle the flashlight. if you omit the wakeup part, the holding won't work.

however there's also support for double tapping which activates the same function as the holding. at first i didn't disable the double tapping. but then during daytime i sometimes noticed that the flashlight was unexpectedly on. that explained why on some days the battery drained faster than the rest. this was quite a mystery for me but slowly i figured it out.

i often quickly check the time: i tap the button twice rapidly. if it's daylight and this enables the flashlight, i simply won't notice. furthermore, often it didn't enable the flashlight on the second tap. it enabled it the next time i've checked the time. i think that's because the second tap enables the flash and suspends the phone at the same time. but the latter action happens sooner. so the phone only enables the flash on the next wakeup when i check the time next time. this is not a problem with the holding because the code enables the flash while you hold the button and only suspends the phone after you release the button.

this bit of the code was quite tricky to get right. most combinations of changing the existing code simply didn't work reliably. in fact, the unmodified existing code didn't work reliably at all. i'm not sure what testing did people do on this. this piece of code is also meant for handling the emergency sos calls if you enable that in the accessibility settings. but it simply doesn't work unless you tap + hold or tap like gazillion times and hope that you manage trigger the code in the right manner. to be fair, if you enable wifi/data and the phone never sleeps then this is probably not a problem. but make sure you don't trust your life to a kaios device in any case.

anyways what worked in the end was this: on keydown, enable the external screen if it wasn't yet and set up a timer to toggle the flashlight. on keyup cancel the timer and turn off the screen if we didn't turn it on with this button. it took me quite a while to come up with this but now it works quite reliably with the tap + hold pattern.

oh and i also changed the default timeout for holding from 3 seconds to 600 ms because the former just felt too long.

if it's any easier, here's how that hardware_buttons.js change looks in the end:

when typing a message, you can press # to switch between T9, Abc, abc, ABC, 123 input modes. the current mode is always displayed in the status bar. however when you switch a slow "toaster" popup drops down from the top and is displayed for about a second showing the new mode. if you want to switch rapidly between modes then you simply don't know what the current mode is because this silly popup keeps hiding the actual state. i found a way to remove this redundant popup:

btw, if you didn't know, if you long press # it switches the language in case you've set up multiple ones. that's quite handy for t9 input. i keep the toaster popup for that case since that's not indicated on top.

the time entry in the alarm clock app is quite weird. what i'd prefer is that i press "1234" to set an alarm for 12:34. instead, i need to press "12<right arrow>34" to enter that. i want the input field to automatically jump to the minutes field after i entered the hours. here's a patch to do that.

phew, that's all the hacks i made. now the phone became quite usable for me. i have a few more generic thoughts. note that i only care about the dumbphone qualities. fancy stuff like camera, music, browsing, apps interest me not. if someone is into that then they are probably better off with proper androids.

the battery level is shown via an icon in the status bar. i wanted to make it show percentages but i think it's a nontrivial change. each tenth level has a separate icon. the icons themselves are in a ttf file. they are unicode glyphs from unicode's private range. it's not impossible to make this work, i just didn't care enough about it. i can live with icons too.

you can check the exact battery percentage in the settings though, see settings -> device -> battery. you don't even need to get into the battery menu, it will display the percentage while you are in the device menu already. once in the settings, pressing left, left, up will get you to a place where you can see the battery after a second or two.

i was quite worried about the battery life. the most promising customer review said it lasts 4 days. that would be annoying but i still gave this phone a shot. i don't need any internet on my dumbphone so i disabled wifi and cellular data on it. i disabled gps too. i even switched the phone to strictly 3g mode since according to nokia's own documentation the battery lasts for 28 days in 3g mode, but only 20 days in 4g mode.

to my surprise the battery life is quite reasonable! at the time of writing i'm on day 20 without charging and i still have 6% left. and i used the alarm multiple times a day each day (with vibration), some calls here and there, accidentally kept the flashlight on for a few hours now and then. otherwise on my light usage days it uses up about 4% battery. i'm quite satisfied with it.

the phone's body is made of very slippery plastic. it slips very easily on a table. i'm not sure this is good or not, it doesn't really bother me.

you can open and close the phone with one hand but requires some practice until you get the hang of it. i feel it's harder than it should be. it's quite odd to me that this got a design award since it feels it could be much better: e.g. some hole on the side with which you could open it easier.

the flip works fine but i feel it won't last 6 years. i feel i'll have to replace this phone sooner than my previous 2g dumbphone. not that i see anything wrong with the design, just a general experience that whatever that moves will break down with time. each time i want to set/disable an alarm (multiple times a day) i have to open and close the phone. i'm sure that will wear the hinge down.

the vibrator on it is quite reasonable too. the vibrator on the pixel4 was very weak. i barely noticed it when it was on a desk while i was in an otherwise quiet room. no such problem with the nokia 2720.

the call quality is pretty good, even in 3g mode. the phone can be set to be adequately loud too. my old nokia 105 was very quiet, so this is a big upgrade for me. it can do loudspeaker and you can attach headphones too. i tried it with a non-mic'd headphone but then i had to continue speaking into the phone. the phone has to be open because it drops the call when you close it.

i don't like the phone's font setting. it's either huge or enormous. it can barely fit a single message on the screen. this is probably also hackable, but i didn't bother. my goal is to use the phone very little so i can live with this inconvenience.

the keyboard seems fine so far, i can type easily. it's pretty much what you would expect from a phone like this. i can't really talk about the quality of its t9, i don't write enough to be able to tell. i haven't really used t9 before anyways. i can easily switch t9's language on the fly by holding down the # key so i might start finally writing via t9.

when closed and you press any of the side buttons once, the external screens turns on and shows the clock for you. every time you do this, it shows the previous time for a very small fraction of a second before it updates to the actual time. i suspect it doesn't bother rerendering the screen while the phone is sleeping which is good. but it also demonstrates just how slow webtech is for simple things like showing the clock. this "update time after turning on the screen" is also present when you open the phone. even there you'll see the previous time for a small fraction of a second. the effect is more visible in this mode since it uses an animation to update the clock's digits. it doesn't really bother me though.

the messaging app is threaded. so the messages from a specific person are in a single screen rather than spread across multiple messages like in my old phone. that's fine although sometimes my message doesn't show up in the thread after i've sent it. i have to quit the app and reopen it to make it appear.

the volume buttons on the side have a quirk too. they set the volume of the current app. if you happen to close the flip when an app is open (e.g. messaging or alarm), then the volume keys will adjust the "media volume". if you want it to adjust the ringtone volume, you have to exit all apps, go back to the main screen, and only then close the phone.

the alarm clock has some quirks due to the phone being suspended all the time. it doesn't trigger exactly at the desired time, it can delay almost up to a minute. and because it starts later, it sometimes doesn't even sound for a full minute, but stops early. if you have a very slowly rising alarm then this might be a problem.

once i managed to completely miss an alarm. i've set the alarm to 05:00 and went to bed. in the morning i slowly became awake and started wondering what's the time. i've pressed the assistant button (that turns on the external screen) and it showed 05:13 and lo and behold the alarm started sounding. so this means i wasn't notified about the 05:00 alarm at all. or if it did notify, it was too short for me to wake up. i don't really mind becoming an alarm a minute or two later. but 10+ minutes is too much.

i'm not the only one describing this problem, just look at these posts and their comments:

fortunately the second thread explains the solution. don't quit the alarm app, just minimize it. press back to minimize the app, don't press the end call button to leave. or don't even bother quitting the app, just close the flip while it's running. i've started doing that and from that point i had no issues. it doesn't seem to affect the battery life.

had i not seen this solution, i probably would have written my own clock app that never stops playing the sound until i stop it. but with the above hack i don't need to bother.

now i can't stop wondering what interface would i make for a poweruser alarm clock app. allow me to indulge on this fantasy while on topic. all i need is a multiline textbox where the line format would be "hhmm[flags] arbitrary_comment". it would be trivial to maintain even multiple alarms in it and would be trivial for the app to figure out the next alarm. i could simple write

to set up two alarms. the n flag would mean no vibration. i could have an x flag to mean a disabled alarm. so after waking up and stopping the alarm, the app would put an x after the wakeup entry:

this auto-x could be prevented with, say, an r flag which would mean a repeating alarm. the ui would always show the next alarm so i can have the confidence that i've set up the alarms correctly. easy peasy and very straightforward to implement. i don't understand why people bother with complicated uis that need megabytes of code to implement the simplest of things.

apart from the big size, i think i'm generally happy with the phone so far. probably won't last forever but hopefully by that time there will be other small 3g phones to choose from.

the battery lost a bit of its oomph over time. over the few past weeks i've tracked how many days it took to get to a given percentage level from 100% given my light usage (alarm clock in the mornings and the occasional calls):

i didn't let it reach 0% since i was actually using the phone and had to keep it charged. the point is that i can easily get 2 weeks out of it but i think initially it managed to last longer. anyway, i'm still happy with the phone. i think i made a good choice here.

i'm now using this phone for over year a now. i'm pretty satisfied with it, no regrets. its battery can still last 2 weeks easily if i barely use it.

i sort of expected that the flipping hinge might break by this time but nope: it still works just as it did on the first day. i guess i had overly low expectations for consumer tech these days.

it now gives me the option to upgrade the operating system to a newer version. but i'm totally not going to press that. i don't want to through this customization nightmare again. fortunately this option is hidden in the settings, it doesn't pester me about it.

in any case, after 1 year of use i can still recommend this phone if someone is looking for a not-smartphone and is willing to invest some time and effort into the necessary customizations.

this phone was all good but i decided to switch back to a smartphone. see @/smartphone for the reason.

comment #1 on 2022-08-01

Hi,

I just wrote you an E-Mail a few days ago but there was a problem with the delivery und just today you activated the comments section :D My E-Mail was in german, therefore I translate the text:

Hallo,

Thank you for the documentation of the tweaks regarding the nokia feature phone. I own the Nokia 6400 4G an I have the typical 'double typing issue'. When a key is pressed, the hardware fires two inputs instead of one thus the software registers two inputs, which is really annoying, so instead of a 'b' sometimes there appears a 'c' etc. I could fix this in the keypad.js by simply adding a must have time of 150ms between two inputs, which solves the problem when typing text (like t9). However navigation through the system (e.g. using the D-Pad, or entering telephone numbers in the homescreen) this hack does not work, I think the keypad.js is not used there. I could not find the relevant *.js file for the system navigation and my question is, whether you have an idea where I can find it.

Cheers from Hamburg

comment #1 response from iio.ie

apologies about the email address, i didn't realize it broke. thanks for letting me know, i now replaced it with an anonaddy email address that definitely works. :)

actually, about a month ago i switched back to a smartphone because i needed lot of gps lately and didn't want to carry two devices. i don't have my nokia on hand currently, so just speculation follows.

iiuc the events start from firefox and then percolate through various event handlers. if so, the question is, is there a way to catch the event at an earlier stage and prevent it from propagating? looking at the files just from my post, i'd try looking around in hardware_buttons.js and see if it's possible to add `e.stopPropagation()` and `e.preventDefault()` to some relevant looking place.

try giving that a shot and let me know if it doesn't work. i can then dig up my old nokia give it a shot myself.