Paymill's iOS SDK provides developers with access to the Paymill API and functionality for integration with iOS devices. The Paymill iOS SDK uses Objective-C. Paymill is an online payment platform that offers web, mobile, and recurring payment options and features.
Square now has an E-commerce API that brings Square services to third party websites. Square is usually associated with its mobile credit card reader and complementary software. With the E-commerce API, merchants can use their own systems with all the benefit of Square's modern payment services.