Wikipedia
Plivo
Plivo, which dubs itself as the Amazon of Telephony, is a cloud based API Platform for building Voice and SMS enabled Applications. It is a Y Combinator-backed telephony startup that offers an API platform for voice and SMS applications, which raised $1.75 million in seed funding from Andreessen Horowitz, Battery Ventures, Qualcomm Incorporated, and SV Angel in December, 2012.