This official Coinkite library is a Python wrapper for their Bitcoin services API. The library works with Google Apps Engine and normal Python server-side application, and also includes a CLI program for use with cURL and the Coinkite API.
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.
Earlier this week, ProgrammableWeb reported that Amazon has released an In-App Purchasing API for applications and games developed for Mac and PC platforms. A Kindle Fire In-App Purchasing API has been available in the Amazon Mobile App SDK since early last year. Amazon has now announced that another tool will be made available for developers to monetize games and applications; Amazon Coins, a new virtual currency for Kindle Fire that will be launched in the U.S. this May.