iOS 4 VOIP SIP Apps?

I use iSip but have no idea if they've updated to make use of the voip multitasking API. Still running 3.1.3 anyway..

 

There are several options now. The most prominent being fring and Nimbuzz.

I'm using Google voice + Gizmo5, and in my experience, Nimbuzz has been hands-down the best SIP app. It has better call quality, the most stable network, and a crisp UI. fring is pretty good too, but has had some on/off network problems. Their voice quality seems inferior even when the network is smooth.

One caveat: if you aren't on either an iPhone 4 or an iPhone 3GS, I can't recommend Nimbuzz, as they limit push notifications (and therefore incoming calls when backgrounded) after 4 hours if you're on an iPhone 3G or iPod touch. Not sure what the reasoning is there . . .

 

It's not iOS 4 compatible (yet), but the one I'm most fond of right now is Acrobits Softphone, which uses the push API for incoming calls.

When an incoming call comes in, a push alert arrives which enables you to bring up the app to receive the call. It has some fairly efficient codecs which are tunable as well to allow for efficient 3G calls. Also supports Bluetooth.

http://www.acrobits.cz

I'm waiting for their business edition, which looks to be a winner.

There are a few SIP-friendly clients that work with push already. The only major benefit you'll get with iOS 4 is the ability to keep that call going while going into other apps.

 

Acrobits is pretty solid, but I'm pissed that I've spent $18 on their software now (the app at full price and the g.729 codec) assuming they'd be adding other functionality like call transfer, etc, and instead they're going and releasing an entirely new app with all the stuff I've been waiting for. It's good software, but I'll be damned if I double-dip for something that should have been there to begin with.

 

Yes, iSip just updated with background support on ongoing calls. So you can browse website or email when you do VOIP calls.