I personally use Lumia 640 XL for about a year and I don’t like this phone. Firstly many apps are not available for windows phone os. Few days before I updated my phone to Windows 10 anniversary update and the phone begins to hang alot. And also while listening music the phone’s back starts vibrate. Camera quality is average. Phone is too big to use. Also I noticed a yellow spot on the screen. I won’t recommend you to buy any windows phone if you want more apps to installed on this platform. Even mouthshut’s official app is not in lumia store. User Interface is very complicated.