I'm on O2 Uk so I'm pretty sure it's a GSM network. I was under the impression that iPhones (at least) could browse the Internet while on a call. But when I switch to Safari while on a phone call I get an alert view saying I can't use data on a call.
And it doesn't matter if I'm in 3G Edge or GPRS (the dot) coverage.
Why is this, and why hasn't it always happened? And more importantly how can I change it?
Best Answer
"GPRS and EDGE will fail at offering both voice and data, and it might be that you initiated the call on an EDGE network"
True, if the network and the device do not support DTM (Dual Transfer Mode, look it up from Wikipedia). For example, Vodafone network in the UK does support this feature, which works with several devices (phones). I guess iPhone is not one of them, though.