You are certainly free to have whatever opinion you want. The companion app was provided free of charge just to aid users (mostly with the Android version which has been available since 2011), and was released long before there was a Windows 10 version of MobileSheets. The implementation is far less complex in the companion app than the tablet application due to it just managing a library that already exists on the tablet. If I released the companion app free of charge and it could be used to set up the entire library, annotate songs, etc, what purpose would there even be in users purchasing the tablet app or MobileSheets for Windows 10 which required a significant investment of time and effort (and still does to maintain it and provide updates)? I would just be giving away the entire application which means I wouldn't be able to run a business. Now that there is a Windows 10 version of MobileSheets, users can view and manage their entire library on their Windows 10 device, then synchronize those changes to the Android device. The app is $13 which is significantly less money than you would pay for most software on your PC. It is also a one-time purchase, all application updates are free, and you can install the app on every device you own that runs the same OS. I don't think the way it is set up now is unreasonable.
Mike
Mike