Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
PayPal - PayPal is the faster, safer way to pay online without sharing financial details, send and receive money or accept credit and debit cards as a seller
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Stripe - Online payment processing for internet businesses. Stripe is a suite of payment APIs that powers commerce for online businesses of all sizes. Use Stripe’s payment platform to accept and process payments online for easy-to-use commerce solutions.
Plivo - Plivo simplifies your customer engagement.
Braintree - An all-in-one solution to accept, process, and split payments in your mobile app or online - from small business to large enterprise.