I have just sold my Lumia 640. Don't get me wrong battery life is excellent, I get home at the end of the day with 70% battery left.
This issue for me was not really apps, all the major apps are there now, its quality of said apps, they are really poor compared to iOS, and a lot of webwraps, my banking app for instance on iOS I can pay bills, transfer money etc, on Windows phone I can only view my balance. They do not have the same functionality, I've found that with a lot of apps for Windows phone, they feel like the first apps that came out on the old iPhone 2G