Stripe Dashboard for iPhone - Track and manage payments on the go

Tango Card - Tango Card bundles an awesome catalog of e-gift cards and other e-rewards with easy-to-use technology and expert program support.

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.

Giftbit - Buy, send and track digital gift cards for your reward and incentive programs.

RevenueCat - In-app subscriptions made easy

Tremendous - Tremendous is a customer and employee loyalty platform that allows companies to reward their customers for surveys promotions and referrals.