I have made website with adifier theme… now how to make customizable applicaton of that website?
Please check the Item documentation hopefully you will get necessary support.
Also you can ask any technical questions to your purchased Item Author. How to Contact Author and let them know. Author will be very happy to assist you.
It depends on if you mean an actual app plus what features, functionality and support you need the app to offer but this sounds like a custom build rather than anything the existing theme is going to be suited to.