HandUp Gift Cards - Give directly to a homeless neighbor on the street
Google Payment API - Enable an easy-to-use checkout experience for customers
Giftcard Zen - Buy a gift card at a discount
Giftbit Payment API - Stripe for gift cards
Gemnote - Handwritten cards & premium custom gifts for companies
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.