The PaySimple Go SDK by Aaron O. Ellis allows to interact with API data to integrate payments and billing features into applications. Available tests to work with account, authorization, customer, and payment.
UTRUST has a bold vision: to be the PayPal of cryptocurrencies. The Swiss startup has a number of APIs in beta, and plans on launching a publicly available crypto payment platform in early 2019. The platform will enable both online and brick and mortar merchants to accept cryptocurrency payments.
Bitpay's API allows for businesses and employees to accept BitCoin for their services and goods. Now with the addition of Newegg to it's repertoire of business affiliates, BitPay is receiving more credence as a leader in the march toward the legitimization of BitCoin as a secure digital payment system.