FaceTime is pretty awesome, but it has one major setback. The only people you can FaceTime chat with must have an iPhone 4 or an iPod Touch 4G.
There are a few Apps out there that help to work around that, and one of the most recent is Tango. Tango will work across both Android and iOS platforms, making it possible for the user to call friends whether they prefer iOS or Android.
This App is recommended for its ease of use compared to Apps such as Fring. It’s of course free, and will make video calls over wifi and 3G.
We tested with Android users and it works just fine.
Check it out: Here