We have three Cubot X6 devices in our family for a year now and now we started facing several problems.
It has a stock 4.2.2 firmware (0.9) and it started acting weird. Facebook bug was present from the beginning and I solved it by using older version of Facebook App. But now Messenger doesn't work as it should too. I often get "Waiting for network..." message and it often crashes (FC). Also, there's a problem with Instagram: after I add a picture, the whole phone gets blocked and I have to remove the battery. And it started installing apps by itself. When I want to uninstall any app, it takes too long (sometimes a few minutes) and after that, another app is trying to install itself. Also, the phone is turning off by itself very often. What should I do? Which ROM should I use? And how to root/flash this device?
The same as first one. This one works good but recently it started having problems with network signal. The signal is very weak and most times it's impossible to make a call or to use internet at all.
This one is running Android 4.4 (KK) and everything works fine but the battery is not calibrated. The battery percentage acts weird.
So, which ROM should I use on this device for optimal performance? How to flash it?