why the adobe photoshop touch not installed to my iphone?

i bought from apple iTunes the apps "adobe photoshop touch" and i face a problem to installe it to my iphone, and the full message appears when i tried to installe is:

the app "PS Touch" was not installed on the iphone "qalalweh's iphone" because it is not compatable with this iphone.

Note: the money i already discharged from my account.

How you can help me?

thanks and best regards

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