I think the ultimate feature an app like this can have is the ability to add coins manually. If there is any way to to do something like giving the app a URL to a coin's market that we are holding so it can pull the price without the developer having to add the coin him/her self! I suspect this may be impossible or very difficult to achieve but man that would be HELLA cool if it could be done, would never have to worry about not having all your coins under one place!