Hi there.!!
I have gone through your requirement for photo printing apps.
I would like to offer you:-
1. Mobile app from where user can make order, see preview, create photo on mug, frame etc. we will use filter option so that user can filter the result of things on which he can print.
2. Admin panel:- here you can see upcoming orders, payment history, user management, profile etc. you can change the status of order.
3. Api:- to communicate with your admin panel server database and mobile app. So that all platform will be synced.
Please revert me back to discuss in details.
Thanks