Hey, just published my take on a simple tool for creating images for the App Store. Most out there are expensive and fully fledged.

This is a first iteration with a base set. FREE to use, and NO SIGNUP. Easily exports a set of canvases for you to upload. It is crude and quickly developed, and obvious next steps would be to add storage of projects and improve the UI as it was not spent a long time on. Anyways, it is free, check it out, create an asset of your own and leave any feedback.