I'm trying to make an IOS app that manipulate layers like in Photoshop desktop version, like copying layers, merge layers, applying filters, etc. I was thinking maybe starting with creating a PSD file with an image loaded from iphone photo gallery, but all I can find is creating layer comp and connecting with Creative Cloud. Does anyone know which framework or header file do the manipulating layers job? I don't need to do anything with Creative Cloud. All I want to do is to edit photos with the frameworks like editing them in Photoshop.