someone is sellling an iphone locally and i e-mailed him but he said he isnt sure which one it is. is there a way to find out if it is the 3g or 3gs? maybe by serial code or something.
cheers matt

Ask if its got the compass app - thats 3GS only.

And to be honest, I'd be wary of someone selling a phone and not actually knowing which model it is - sounds a bit dubious.

The 3GS has silver writing as well as apple logo on the back. The 3G only has a silver apple and grey writing

Baz

Ask them what the model number written on the back of the iPhone says (or ask them to send a photo of it). It will be written in small writing below where it says iPhone and the memory capacity.

A1203 is original iPhone (4GB or 8GB)
A1241 is iPhone 3G (8GB or 16GB)
A1303 is iPhone 3GS (16GB or 32 GB)

If you will be wanting to unlock it to use with non-O2 networks then you may also want to find out some other details about the phone too. For example if it's a 3GS and they have updated it to firmware 3.1 then you won't be able to unlock it - at least not until the dev-team manage to crack the latest version. If in doubt I would ask them not to update it just in case (if they haven't yet done so).

cheers