Okay, so I downloaded Skype - the new P2P voice-chat app by the guys at Kazaa - and I have to say how freakin' rocking it is! Moof and I spent an hour today chatting with it and it was completely comfortable, glitch-free and high-quality. Very cool - we're both waiting for the conference version so we can do a multimedia #mobitopia!
And that lead to random mobile application idea #456: Someone needs to wire this up with my mobile phone. I mean *now* not some day in the future. Here's how I see it. First a native Symbian app on the phone accesses the Bluetooth connection to a PC and streams voice each way. At 1650 bytes/sec for GSM-encoded voice, Bluetooth has more than enough bandwidth to handle it. This would allow your Symbian device to act, believe it or not, as a phone. On the PC side, a Bluetooth server sits and acts as a gateway between the serial port and the P2P voice app.
Now - I don't want the client to just be a dumb headset with a mike. I want to be able to start the app up, get access to my normal address book, choose someone I know has the same setup, and to attempt to make the call via BT. Now if the call doesn't go through, I want it to swap to a normal GSM connection and then dial that one.
There's already a company out there that's developed a proprietary VoIP app that'll work with WiFi and Bluetooth gateways. What I'm talking about is a basic Symbian app and a custom PC-client for the P2P bit. Native Java could handle that part.