Download Miles & More APK

I downloaded this app because for what I understand, the online mileage calculator is no longer functional. So I download it and find the mileage calculator. It took me 10 minutes to enter all the info. It asked me all flight details, which I had to go and grab in my Swiss App. But whenever I closed the Miles&More App to open the Swiss App to look up information, the data I had previously entered in the Miles&More App was gone. Eventually I wrote down all information of all flights on a piece of paper in order to enter it in one go in the Miles&More App. After doing that -- quite a drag -- I got an error message that "the mileage could not be calculated due to a system error". Now I'll have to call the Senator hotline on the phone and spend another 15 minutes or so to find out. Also the App asks the Booking Class for the mileage calculation, but the Booking Class is not listed either in the Swiss App or on the flight Reservation confirmation... Suggestions: just put the mileage value right on the confirmation, as well as the booking class, and list that same information in the Swiss App. Seems like that should be easy to do. This has been extremely annoying!