when are we going to stop comparing phones to one another? PLEASE PLEASE PLEASE, i beg you, compare the specs of the 950xl and the 640, better screen, processor, camera, better everything.... the same goes for the 1520, except that one has a monster battery. You will not not not NOT get the same battery life between the two. My battery lasts a solid day on .29 on my 950XL. If you want to spend all day surfing the net on your phone, then you need to turn the display down to 25% and every feature off. Apples to oranges wont get you what you want. My old Nokia 5200 lasted 3 days, this 950XL is a piece of junk. Thats the logic, pretty much.