I have a G1 Dev phone with original setup purchased from Google in Summer 2009.
In germany I just used it with a Vodaphone SIM card without any credit so that the phone would boot and let me access WiFi and apps on the phone. This was to avoid signing up for any 3G data services.
For telephone calls I just used my old reliable, very unsmart Nokia.
Back in the UK, I put my UK T-Mobile Sim card in the G1 phone and used it for phone calls as well. In some ways it not as good at basic telephoning as my old Nokia.
What I have noticed is that my PAYG credit declines steeply - £5 / day for very few calls & texts. I later noticed that I was accessesing data services when not connected to WiFi. The UK card must support data.
In the settings I have disabled data services, told it to use 2G to save battery and generally tried to turn off all data access except voice calls & WiFi. I can't seem to turn off data services without also turning off WiFi.
Q1 Is there a way to do this?
Q2 Where can I find the OS version? I expected to find something like "Android 1.5" under About Phone but instead find a Model Number, Firmware version, Baseband version, Kernel version, Build number, none of which include "1.5"
The closest is
Build number: dream_devphone-userdebug 1.0 UNLOCKED 116222 te3st-keys
Kernel version: 2.6.25-01843-gfea26b0
Q3 Will this G1 phone support Android 2.2 ( and later versions), within the capabilities of the h/w, if I install it on the phone?