Read http://arstechnica.com/security/2015/11/new-type-of-auto-rooting-android-adware-is-nearly-impossible-to-remove/
One wrong app choice and you can't remove the nasty.
That's why I can't recommend these today.
Hi guys!
I'm going to buy a new smartphone for myself
I've searched some of the best smartphones in 2015, such as Iphone 6s/6s Plus, Samsung Galaxy S6 Edge/Edge+, Nexus 6P, Xperia Z5/Z5 Premium and others
What smartphones would you buy in those following above?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic