eBay4R is a Ruby wrapper for eBay's Web Services SOAP API. Has ease of use and small footprint. Instead of 40-50 line examples eBay gives you in C# and Java, with Ruby and eBay4R, examples are 5 lines or less.
Paidpiper, mobile payments processing provider, offers its unique mobile payments platform via the Paidpiper API. Instead of relying on network security to ensure reliability and compliance, Paidpiper's unique approach secures the smartphone making the transaction to prevent malfeasance and fraud. By securing the smartphone itself, no need for additional POS hardware becomes necessary.