Simplenote uses Simperium to store and sync notes across iOS, Android, Mac, the web, and an ecosystem of 3rd-party apps. The Simperium libraries handle all the networking so developers can focus on building a great user experience.
The current version of the Simperium API does not allow for 3rd party development of Simplenote apps at this time. We will update this page in the future after we add support. Thanks for your interest!