Sailfish OS is a Linux-based operating system based on free software, and open source projects such as Mer as well as including a closed source UI. The project is being developed by the Finnish company Jolla. The OS first shipped with the original Jolla Phone in 2013 (its sale stopped in 2016, but it was supplied with software updates until the end of 2020), then the Jolla Tablet in 2015 and from other vendors licensing the OS. The OS is ported by community enthusiasts to third-party mobile devices including smartphones and tablet computers. Sailfish OS can be used for many kinds of devices.