MESSAGES TO THE MODERATORS: There isn't a v0.11.1 alpha for versions affected, as it's the only build available to iOS.

I think it's self-explanatory.
With no other way to upload a skin onto the phone, I decided to upload it onto imgur and download it off there.
http://i.imgur.com/JeOwkz8.png

After downloading it onto my photo albums, selecting it would result in the game saying "That's not a Minecraft skin. Silly".
(Which by obvious deducing would mean that it's an invalid format/file.)

I then tried downloading it straight off my Minecraft avatar, which is http://textures.minecraft.net/texture/46e54b38ca489583f5f3e69cd0f25c50adcf29253fc5169dc6abafdc4770

Again, it came up with the same error.

Edit: I tried a 64x32 skin (http://s3.amazonaws.com/MinecraftSkins/aytimothy.png) and the same problem persisted.