Simplenote uses Simperium to store and sync notes across multiple app platforms. The Simperium libraries handle all the networking so developers can focus on building a great user experience.
Contribute to Simplenote
All of the Simplenote apps are open source and ready for your contributions! You can find the source on GitHub:
Electron (Windows and Linux): https://github.com/automattic/simplenote-electron
The README files on each of those repositories have all of the instructions you need to get started!
Third Party Applications
It is currently not possible with the Simperium API to support third party applications for Simplenote. While we work on fixing this, we’d like to hear from you if you have a great idea for a Simplenote app. Please contact us and let us know!