This is an unofficial Groupon PHP SDK for the Merchant API. Working with this kit could help developers to create mobile applications related to coupons and discounts that can benefit groups of customers. The API affords interaction using REST protocol. Authored by Abhinav on GitHub.
SumUp, a mobile payments rising star, recently announced an API that allows third party apps to accept credit card and cash payments without leaving the app. Prior to the API, SumUp users and customers were required to use the SumUp app in isolation from the merchant app to utilize the slick mobile payments platform.