Sailfish OS 4 has been released, but who is this mobile OS for anyway?

Jolla has released Sailfish OS 4 which includes a new browser, better Android app support and many tweaks. The Finnish company has been around for years, but who do they actually make their alternative operating system for?

The new version of Sailfish OS includes a new browser and sandbox for apps: an overview of changes can be found on the homepage of Sailfish OS. It concerns Sailfish OS 4.0.1, also known as Koli, the fourth major version of the mobile operating system.