Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Cash App - The easy way to send, spend, bank, and invest.
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Facebook Pay - Send money to your friends via Messenger
Plivo - Plivo simplifies your customer engagement.
PayPal.Me - Request money using your own personalized URL.