[kabouseng]

Correct, the GSM modem do indeed vary its transmission power depending on the RSSI (received signal strength). Also with low signal strength packets get dropped, so needs to be retransmitted, which also drains the battery more.

[antoaravinth]

This is interesting, do you have any resource on this topic?

I wonder how a phone with dual sim can handle battery life? Thats totally an interesting problem to solve. I use micromax which is a dual sim and the battery life is pretty good, last for a day.

[0x0]

Yep, and it's very obvious even in different parts of the city for me. In one office, the phone is still at 60-70% after a day's work, while in another it's usually dead by the end of the work day.

[s_kilk]

Which may account for the wild variance in reported battery life from different people with the same model of phone.

[exelius]

Can verify this. I was working for a client who was located in an area that had maybe 1 or 2 bars of LTE service - my phone was below 20% at the end of the day if I didn't charge it. Now that I'm in a big building with AT&T microcells, I get 5 bars LTE so my phone is at over 50% by the end of the work day.