A sad notice today. I've retired Shopless from the AppStore. The reason is simple: I can't afford the costs of the server that stores and syncs the data.
I'm happy with the acceptation of the App. It was developed with my needs and since today it helped me and others (to my surprise) in the process of shopping, so I think it worked as intendeed.
In the future I will think twice before developing an App with a server side component and trusting the live of the App in to one of this magical backend services.