Sailfish is THE best & THE most secure operating system the world has for a mobile phone. 

I've been friends with Jolla since their first phone hit the market & have been a fan ever since. I've run their operating system on a variety of phones that now litter one of my drawers. Bar their new device my fav was always the Nokia and then it changed to be the Sony.

I got an offer from them that I couldn't refuse. 50 Euros. Hardware included. I jumped at the chance. Since then I've been a loyal user.