You own the rights to the concept in your Excel spreadsheet, your application, and all user-generated data created through the App. XL2App retains the ownership of the IP for our blocks and technology, pre-designed page and element templates that we use across multiple projects. 

Yes, you can come back to us at any point after the initial build for additional work. You can request ad-hoc updates or sign up for a monthly plan, which will come with a certain amount of team capacity.