There’s a stunning VoIP and IM service named fring, for your 3G cellphone running Symbian or Windows Mobile (hopefully more will be supported later, and 3G isn’t strictly necessary). Use it to phone your fring-using friends for “free” (paying only internet bandwidth, which is cheap, especially compared to phone calls). fring can also dial through your Skype account (including using SkypeOut), your Google Talk account, various SIP accounts, MSN messenger, etc. (If you’re happy to give them your passwords.)
Perfect… except if you use MTN (South Africa). Which I do…
MTN technically forbids the use of VoIP over their network, and they reserve the right to charge you R25 per megabyte if they catch you. (I estimate that to be close to standard cellphone rates, except, they might charge both parties in the conversation, if both are MTN customers.) They also reserve the right to terminate their agreement with you with immediate effect. It all sounds very scary, but they have not actually done so, yet. They simply reserve the right to… For now? I will limit my use, so that if they hit me with R25 per meg, it won’t be the end of the world. I hope if they cancel my contract, I can still take my number with me.
I have tested the SkypeOut functionality, the round trip time was about 2 seconds (so one second either way). Yes, that is indeed a noticeable lag, but it is usable. And it helps you practise patience. And I’m sure fring to fring round trip time is better. I will test it some time. (For international calls, R25 per meg is actually a good deal, I think? Then again, I can usually just use Skype at home, on my laptop, avoiding the MTN threat altogether.) And then there’s the IM functionality, if you want to be always-reachable at the same address.
Supporting Google Talk means you should also be able to contact your mxit buddies (using IM), without having to use mxit yourself. (I don’t want to give fring my Google password though… oi… tricky. Voice calls are tempting, but I suspect most “Google Talk” users are just Gmail users like me, and can anyway not receive voice calls.)