There are files that fail to decompress on Mac or iOS. Even using open source for iOS, they all fail. Clicking on the MacBook to open it fails. However, some compression programs on Mac or PC will successfully decompress it. Is there any way to forcefully open or decompress such a compressed file (Zip)? I tried the Apple Archive method, but that method also fails with an error now. (Personally, I would like to be able to force such a file through the Apple archive.)

I haven't developed an Apple Watch app yet. I have an existing app for sale. Users of that app sometimes send me requests for functions using Apple Watch in the app by email. Considering future maintenance, I would like to sell the Apple Watch app as a paid app. However, I know that watch app support cannot be turned on/off by in-app purchases in existing apps. Is there any way for the standalone Apple Watch app to communicate with my existing paid/free apps?