hello. my daily driver phone is a 2013 LG G2. it's my favorite device and i intend to use it as long as i can.
unfortunately, 3G services are ending soon in my region. this device is 4G/LTE capable and even supports VoLTE on the stock firmware, however with a (AOSP-based) custom rom, VoLTE is non functional. data network and sms works with 4G, but calls switch to 3G.
to keep it functional as a phone, right now my only choice is to install the stock rom. unfortunately the stock rom is terrible compared to lineageos. latest stock rom is at 5.0.1 lollipop and is poorly optimized, has ram leakage issue that needs reboot every few days or so. i'll have to install 4.4.2 kitkat to use it well, and that means saying goodbye to all modern apps...
recently i've seen some people make VoLTE work by reverse engineering the IMS(?). such as LG V30, LG V50, LG V60, Samsung Galaxy S9/S20/S23.
while these are all newer than my device, at least there's an example unlike just a few years ago. since my device is older than when AOSP started officially having VoLTE support i suppose my device's implementation would significantly differ, though i hope it's similar to those newer LG devices.
thus i'm looking into developing IMS for my device's lineageos, any pointers are appreciated. thanks.
I unfortunately can't help, but I wanted to suggest that you may want to also try posting on the LG G2 section of the xdaforums about this. It'll help it get more eyes on it - especially of those that are familiar with and interested in that model and may be interested in the same thing and/or able to help with what you're wanting to do. They're all about stuff like this over there!
I wish you luck! I have a different phone, but I also have to stick with the old stock firmware for the same reason, so I feel for ya!
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