UHS means the card is fast, in a simplifying way.
That means the 520 supports UHS Cards, but it won't reach the maximum speed the card supports, it will only reach the maximum speed the phone supports.
So, Lumia 520 supports ANY microSD up to 64GB.
Lumia 535 has smaller text than 640
Both Lumia 640 and 535 have the same screen size (a 5 inch screen.)
The 640 has a 720x1280 resolution with 294ppi, and the 535 has a 540x960 resolution with 220ppi.
Why on Earth is the text on the 535 smaller than the 640?
The 535 can fit almost twice the...
Re: Lumia 1520 - Images stretched at corners
I guess that's Lens Distortion. That's normal in Photography. It should be a little distorted around the edge of the frame.