How can I split photo and create a customized start screen?

[GiacomoRock]

Hello everybody!
I would like to know which app can split a photo into a lot of tile of different dimension... As you can see in this image posted by Nokia on facebook:


I actually use this app:
Photo Tile
but it doesn't satisfy me...
It's not the same used by nokia, because with this one you can't split the image into tile of different dimension! (small and medium-sized)

Sorry for my bad English! I'm from Italy.
Thanks to all those who will help me

 

[Nokia Boy]

It might be a photo edit
btw i found this app,try it Skinery Themes | Windows Phone Apps+Games Store (United States)

 

[GiacomoRock]

I don't think it's the one I'm searching... By the way: "Sorry, you can't get apps in this region. Please check the Store in your region"

 

[Mohd Saif]

I think it's called Picture cutter