The reason why you need to select the map is because you could potentially have multiple maps of the same area and you could be on visible on all of them, however, the app doesn’t know which one you want to select to view on, so it lets you choose. Unfortunately, it won’t automatically open a map to your location either.
Other users will also open Avenza Maps and go to the My Maps list to organize their maps or map features or they want to open a map they aren’t on to add map features or use our GPS tools. Those are some of the reasons why it doesn’t open up to a map your location is on.
I hope that answers your question, if you have any other questions feel free to post a reply.