toolani - Cheap international calls
Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...
KeepCalling - Best Rates for International Calls. No Contract, Expiry, or PIN. Use Any Phone, Smartphone or PC.
Talkatone - Android App on. Google Play. Stop paying for cell minutes, texts & landlines; Turn your iPad or iPod touch into a phone; Call/Text even in areas with bad cell coverage; Call/Text when travelling without paying for expensive international minutes.
mytello - Cheap international calls via local dial in number at very attractive prices.
TextMe - TextMe is a free calls and messaging application at both local and international levels.