Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...

Ameyo - Ameyo is a powerful and highly flexible IP-based contact center software that lets you have a personalized interaction with every customer across multiple channels, thereby driving customer engagement to a level par excellence.

TextMe - TextMe is a free calls and messaging application at both local and international levels.

Aircall - Aircall is a call center software of a new generation designed for fast growing companies. Setup instantly and integrates to your CRMs

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.

Five9 - Five9 provides cloud-based call center software for sales, marketing and support.