Giftcard Zen - Buy a gift card at a discount
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.
Wirize - Payment checkout for freelancers
PayPal.Me - Request money using your own personalized URL.
Google Payment API - Enable an easy-to-use checkout experience for customers
Bonsai - One platform to streamline your entire business