Simplenote is a free text editor for iOS, Mac, Android, Windows, and Linux. Automattic, the developer behind WordPress and Simplenote, has made every version of the app available on GitHub as open source software.

Today’s announcement is good news for people who enjoy Simplenote’s interface, unlimited storage and syncing, easy publishing functionality, but want to customize it further to suit their needs.

The app includes support for Markdown, as well as syncing across multiple platforms. The Simplenote experience is all about speed and efficiency. Open it, write some thoughts, and you’re done. As your collection of notes grows, you can search them instantly and keep them organized with tags and pins. You can also share notes and publish them for other people.

Simplenote is available as a free download from the iOS App Store and the Mac App Store. The app requires any device running iOS 9.0 or later / Mac OS X 10.8 or later.

The source code for all of Simplenote’s apps is now available from Automattic’s GitHub page.