TextNow - TextNow is a mobile virtual network operator (MVNO) that provides a free phone service to users by using other cellular networks coverage.
Callmama - Get cheap international calling, international virtual number, Call Mama Gives an added advantage to send message and make calls to non-user of Callmama App.
Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...
CallHippo - Easy to use Phone System with World-Class Support
Burner - Disposable phone numbers -- now with MMS photo support
KrispCall - Virtual cloud phone system for business