2. Design Your Own Gadgets/Suit
This is another idea that would be really cool to see someday. Batman is well-known for his gadgets, and how he's able to solve pretty much any situation thanks to them. Same thing goes with his suits, since he has one for pretty much any problem he gets into. He designed each and every single one of those instruments, and all of them work perfectly. Making an app in which you have to design your own instruments (from its look, to the function, which materials it would require, how many charges it can hold) and suits (from the color of it, to the armor it would have, what conditions it could withstand and how many items you can carry with it) would be incredible. How cool would that be, right? Not only that, but they could add some kind of easter-egg artifacts, like, I don't know, Adam West's Shark Repellent or Nite Owl's suit, something like that. This one needs to happen soon.