Always I have first choice microsoft lumia because these phones are vry good for a professional person. In this phone u will get all the engineering data or apps easily. Its build body is too cute. I love all the back covers of microsoft lumia 640. In android u wont get colorful back covers like lumia. Lumia 640 camera is too good 13mp. And front also awesome 5mp. Its good to take selfies. This lumia h 8.1 window with a gd speed. If u have lumia set 640 than need not to buy any laptop or personal computer.