Hi,
since the retina display and the HD Ressources in DPS App Builder, there is a problem with the sizes of the files you can add. The HD Ressources are limited to 2 MB.
But unfortunately, a 1024x1024 px Icon in PNG has already more than 2 MB and you can't step to the next point in DPS App Builder as you receive an Error Message to provide a lighter file.
Please change this size limitation. Its obligatory!