(2024-11-11) CAT S22 Flip: a keypad Android flip phone done almost right
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Since KaiOS flopped (and I'm sure it's already pretty safe to declare that),
the question of finding a decent keypad phone with modern application
support is relevant again. And things like Xiaomi Qin1s or AGM M7 are not
exactly the kind of support I'd have expected in 2024. Luckily, Bullitt
Mobile to the rescue once again, and the model that still can be found new
(although sometimes unofficially), CAT S22 Flip, seems to deliver the very
experience I was looking for. It has a Qualcomm Snapdragon 215 (although its
Fastboot menu was compiled for 430), 2 gigs of RAM and 16 gigs of built-in
flash storage with, of course, ability to expand it with a microSD card
which I surely did. It runs Android 11 Go Edition with some (unwanted but
removable with root) T-Mobile/Sprint customization, and it looks like the
firmware comes in two versions: 29.04 and 30.03, the latter being what my
device has, and TBH I doubt this model will get any more updates in the
future. And here's where things get interesting: it has both a physical
keypad and a touchscreen, although you'd never guess it had one from the
pictures. Hence, both Gboard and KikaInput are preinstalled in the firmware,
and, thankfully, I managed to replace both of them with Unexpected Keyboard
and Traditional T9 respectively.
Hardware-wise, this phone is, as Action Retro would say, "not too shabby",
despite only supporting a single SIM in the nano-SIM form factor. The lack
of a 3.5mm audio port was compensated with an adapter in the box (which, by
the way, you will need if you want to listen to the FM radio), and the lack
of wireless charging was compensated with a two-pin dock connector on the
back. Good luck finding that dock though, but you still have an option
nevertheless. And let's not forget a really useful flashlight, which has
recently almost replaced my regular flashlight for the kind of tasks where I
have to wander around the house at night. My only real complaint about all
this is the size: CAT S22 Flip is almost twice as thick as CAT B40 while
being just as wide and only a couple of centimiters shorter than it... in
the closed state. You won't really understand how humongous it looks until
you see it in person. Granted that it's heavier than B40 as well... I think
you get the idea. I understand that this chungus houses a removable 2000 mAh
battery but still, they should have consulted whoever manufactures Sigma
X-Style 31 how it should be done. So let's hope that all this extra size and
weight is for some impact and ingress protection the brand claims for this
model.
To be honest, rooting and debloating are the first things one should do with
such a phone, although it's not without its quirks. The XDA forum has a
guide ([1]) on how to root the S22 Flip, but my mileage varied a bit. First,
the guide doesn't tell you what to do if the "OEM Unlocking" option is
greyed out. My device already came here carrier-unlocked (although the
T-mobile branding is all over in the firmware) but I still had no option to
toggle the OEM unlocking until I entered my Google account. Afterwards,
beware that the firmware has encryption setting turned on, so running
"fastboot flashing unlock" will erase your userdata partition. Then you can
follow the guide, although I didn't have to patch the vbmeta partition
either. Maybe I'll post the patched v30 boot.img somewhere alongside the
simplified guide, we'll see.
The post-rooting steps though are the very thing where one can screw up very
easily. Of course, I installed F-Droid (and FFUpdater and Obtainium via
F-Droid) and a number of essential things, the De-Bloater application being
among them. This is a Magisk module to move system applications out of the
visibility while not physically deleting them. Nevertheless, it still can
render the system unbootable, so be careful. By the way, you can find TWRP
for this device, but I tested it and found out that it will do more harm
than good, so I don't recommend it. Here's the list of packages (as they're
called in De-Bloater) I debloated this way and the system still boots and
every basic function works:
* 12-Key Keyboard
* Android Setup
* Calculator
* Calendar
* Camera
* Carrier Device Manager
* Carrier Hub
* Cat phones
* Chrome
* Clock
* com.android.providers.partnerbookmarks
* Data Restore Tool
* Digital Wellbeing
* Drive
* Duo
* Files by Google
* Gallery Go
* Gboard
* Gmail
* Google Assistant Go
* Google Contacts Sync
* Google Go
* Google Location History
* Google Partner Setup
* Google Play services
* Google Play Store
* Google Services Framework
* Google SetupWizard Customization
* Google Speech Services
* Google TV
* Keep Notes
* Maps
* Market Feedback Agent
* MCM Client
* Messages
* Mobile Installer
* Speech Services by Google
* T-Mobile (AdaptClient.apk and TMobile.apk)
* T-Mobile Diagnostics
* TDC
* TMO-RSU-Common
* TMO-RSU-Sys-Service
* Unlock
* Visual Voicemail
* YouTube
* YouTube Music
Quite a lot to remove for such a device, if you ask me. I even considered
moving to a LineageOS setup (yes, there is one for S22) but it's not quite
ready yet, as it has no support for the programmable side button and, which
is more important to me, for the external display. Also, do not remove
Quickstep even if you install an alternative launcher: you'll lose the
ability to switch and close windows. Maybe this stock Android distribution
just was built this way, who knows.
Other than that, it's a pretty "normal" Android 11, so you can install
whatever you want, of course, remembering about the amount of RAM and
storage here. I, for instance, switched to my favorite Android launcher for
small screens, KISS Launcher, and likewise replaced a lot of the
aforementioned debloated stuff with its FOSS counterparts: Files by Google
=> Amaze, Gmail => Thunderbird (former K-9 Mail), YouTube => Clipious,
YouTube Music => InnerTune, Maps => OsmAnd~, Gallery Go => Fossify Gallery
and so on. I think F-Droid is an excellent starting point to look for such
replacements.
Of course, all that is fun and games, but how about the *real* stuff some of
you come to this phlog for? Well, for starters, let's list some secret codes
(where applicable, only the mnemonic is provided):
- *#*#INFO#*#*: standard Android info
- *#*#LOG#*#*: Qualcomm LogKit launcher/stopper
- *#*#ENGMODE#*#*: a comprehensive engineering menu with netmonitor and other
stats
- *#*#0202#*#*: some TFT stats or version
- *#*#02#*#*: device info
- *#*#2846#*#*: version info and test toolkit
Okay, let's see where the IMEI is stored in there. And it MIGHT seem like
it's stored in the plain ASCII in the partition called "factory" at the
offset 104 (0x68), but that's an illusion, it gets overwritten there from
somewhere else. Nor is it stored in the fsc, fsg, modemst1 or modemst2
partitions. So where is it? Well, the answer seems to be not so pleasant:
it's stored in the "persist" partition, in the encrypted form. Namely, the
mounted path of the directory is /mnt/vendor/persist/data/keymaster64, and
inside this directory there is a "keymaster64" file that contains the index
of all encrypted factory information files, including the IMEI number, in
the same directory. It's the Qualcomm KeyMaster, baby! Well, it looks like
I've got myself another rather long-term research target in addition to the
Pixels.
So, what's my overall first impression about CAT S22 Flip? Well, about 7/10.
It definitely is usable (especially once rooted and debloated), it
definitely is rugged, it definitely is "smart", but it also is a little too
bulky in size and too non-free to my taste, considering not only IMEI
encryption but also the amount of work required to debloat the stock OS and
lackluster support for third-party builds like LineageOS and TWRP. As I
said, it makes a nice research target for the future efforts and a nice
Android workhorse for the present time, but I'd also like to find something
that would even more adequately respond to my needs. Something
Android-based, maybe with a keypad/touchscreen combo as well, but slicker
outside and friendlier to folks like me inside.
--- Luxferre ---
[1]:
https://xdaforums.com/t/tut-root-how-to-root-cat-s22-flip-on-version-30.46269
1/
