!4G feature phones
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agk's phlog 
13 July 2021 @ 0052
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updated 29 July @ 0054
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written on x61 in the kitchen
waiting anxiously for labor to start
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I love my Nokia 2610 feature phone. Fifteen years 
old, it's a rugged, dependable, nondistracting,
tiny brick. It feels good in my hand. The Series 
40 OS doesn't do telemetry. Battery life is fine 
for a trip out-of-state with no charger. I can 
talk, message (SMS), look at the calendar, and 
use a calculator. There's no camera. It cost 
$20. The replacable battery is a standard, cheap 
BL-5C. Its first battery lasted 12 years.

I'd keep it 15 more years as my only handset if 
2G carrier equipment wasn't being retired. A few 
months ago calls started dropping into send-only 
simplex in my work parking lot. I transmit and am
heard by the other party, but can't recieve and 
hear their voice. On the road calls get real quiet.
I leave service areas increasingly often.

It would be nice to replace it with a similar hand-
set that would work on cellular networks for the 
next fifteen years. In my market there are only 
expensive designer mobiles and feature phones 
running KaiOS. I'm more into the new 4G low-end 
feature phones for India, China, and subsaharan 
Africa.

 Designer handsets
 -----------------
Developed by designers with no track record of
making mobile handsets, these expensive luxury 
goods are largely feature-compatable with $30 
feature phones. They offer 2G/3G/4G-LTE connect-
ivity on North American and European spectrum.

PHONES HOME: The Punkt MP-02 is a $350 rugged, non-
distracting brick that looks like it would feel 
good in my hand. The display is transflective. It 
has a Signal-compatible messenger. The user inter- 
face is mostly black-and-white text-only, which I 
like. The OS is stock Android (AOSP 8.1). It phones 
home regularly to Google and its Shenzhen firmware 
company. There's no way to turn telemetry off.[^1]

TOO BIG: The Mudita Pure is a $370 feature phone 
expected to ship in Nov 2021. It appears to be 
rugged and nondistracting, but almost as big as a 
Samsung Galaxy 8. The display is e-paper, which I 
like. It has a bespoke OS.

TOO LIMITING: Justine Haupt's Mk2 rotary cellphone 
is a $390 handset expected to ship in early 2022. 
It is gorgeous and small. It recieves texts and 
makes calls.

 KaiOS and Series 30+
 --------------------
KaiOS is the descendent of FirefoxOS on low-cost 
4G feature phones. It manages power better than 
smartphones, but not as well as Nokia's more basic 
Series 30+ OS. KaiOS apps are written in html and 
css. Phones ship with Google voice assistant, You-
Tube, and Google Maps. Displays are bright, color-
ful, and distracting.

KaiOS is basically a web browser. It's hackable
with adb and info from bananahackers.net. With elbow 
grease I could maybe pare it down and make it more 
like my much-loved handset, or extend it with xmpp
messaging, sip calling, and ssh. No tweaking will 
make a KaiOS phone smaller, though.

Nokia 105 and Nokia 110 phones are being released 
this summer with 4G VoLTE connectivity in China and 
maybe India. The $35 feature phones run Nokia's
delightfully basic Series 30+ OS. At least some will 
work on US GSM-850 bands. These are 4G successors 
to my Nokia 2610. I'm keeping an eye out for a way
to buy one in my country.

 Added 29 July: Mocor RTOS
 -------------------------
Visiblink@zaibatsu suggested I consider the AGM M6. 
It's the current favorite of Jose Briones, mod of
the very cool dumbphones subreddit. The phone looks
great, except its size---big as Mudita Pure, nearly 
as big as smartphones. M6 runs Mocor, a RTOS for 
Spreadtrum devices that I think is based on Android 
4.4. I'm watching for smaller 4G Mocor phones. Thank 
you visiblink!

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 [1]:neflabs.com/article/punkt-mp02-security/