What it does: For those of you unfamiliar with the company, BigTinCan is an Australian "call back" voice provider that lets users hook onto its VoIP servers by contacting them through their standard phone networks, thus letting them place long-distance calls for relatively low prices. This particular application gives BigTinCan users the ability to call or SMS users in your directory simply by clicking on their pictures. The app can also sync up with Twitter to provide others with real-time information about people you're calling and messaging, although the company never explains why any sane person would want to do such a thing.
Who developed it: BigTinCan
What it costs: The app is free, although you'll obviously have to pay BigTinCan money every time you make a call using the app.
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