This is very nice phone. it have Windows 8.1 and his upgrading is Windows 10 in my phone have Windows 10 it is better then Windows 8.1 some feature is amazing like Lumia cinemagraph, Microsoft windows store, groove music and developer mode.
The Developer mode is very Amazing in this windows 10 phone. In this mode you connect this phone with your PC and install Android apps in your windows 10 phone.
Windows phone is really amazing then boring Android operating system. I like this phone. so guys purchase this phone its very amazing.