B2G OS!

Mobile-optimized with the flexibility, ubiquity and stability of the Linux core and a cutting edge user experience built with the renowned Qt™ platform.

Windows 10 Mobile is a mobile operating system developed by Microsoft. Some features include : Live Tiles, Kid's Corner, Photos + SkyDrive, Rooms. It also allows you to Take your Word docs, Excel spreadsheets, PowerPoint presentations and OneNote notebooks on the road, and automatically upload every photo and video you take on your phone to SkyDrive for safekeeping (with a choice of full or lower resolution).

Tizen is an open source mobile and device operating system based on Linux developed by Samsung and Intel.

Plasma Mobile turns your phone into a fully open hacking device, just like a PC. You can join us to start building new mobile experiences now.

OnePlus launches their own Lollipop-based ROM. Available now for download: http://downloads.oneplus.net/

Astian OS, is an operating system based on Firefox OS, developed by the Astian Foundation. Astian OS was born in 2016 with the objective and mission to innovate in the world of mobile operating systems and to continue the work of having a mobile operating system developed with HTML 5, CSS, and JS. Astian OS is scalable open and is a platform that allows to interact with the devices from the web with great orientation to IoT.

QtMoko is debian distribution for Linux based SmartPhones, like Openmoko Freerunner and Goldelico's GTA04 phone. Phone and user interface is based on QT Extendeded formerly known as Qtopia..

H5OS is a mobile OS based on Firefox OS developed by Acadine Technologies.