What would be the reason to have an app rather than just using the mobile site? If it is that you want to use EYB without internet access then you would need to have a huge amount of data stored in the app on your phone - this would be a storage and data hog. EYB is a very large database so in order to access what you have when you use the website there would be a huge drain on your phone and data plan.
If you just want to be able to tap an icon on your phone home screen to access EYB (as you do for apps) that can be done now. This is explained in Help.
Or was there another reason I am missing?