From Apple:
"Available on macOS Mojave
When users on macOS Mojave first open a notarized app, installer package, or disk image, they’ll see a more streamlined Gatekeeper dialog and have confidence that it is not known malware.
Note that in an upcoming release of macOS, Gatekeeper will require Developer ID signed software to be notarized by Apple."
You have to NOTARIZE your EXISTING (already) software, for your new customers running macOS Mojave in order they to can use it!? NOTARIZATION, lets say that (just) attaches a ticket to your already SIGNED software - (NOTARIZATION) not useful software functuanality for the customer that involves time and effort!!! By my information macOS Mojave requires and allows only 64bit apps... I will postpone its usage to the end of the world where that depends by me. It is Apple commercial policy imposing the usage just of their own products against all native cross-platform technologies, destroying businesses and in this way against the reqular Mac Users, but without posts like this They will never know!
With other words: The Customer can not update to the latest software versions, because Apple disallowed 32bit apps store submitions and the native cross-platform development environment vendors are still not ready with the 64bit compilers and graphical user interfaces. According to their Road Map, they will be ready at the end of 2019. AND Because of the GateKeeper the software (in Apple store) can not be downloaded by the new Customer... But the taxes are paid!
From Microsoft:
"App Policies: 10.1.4 Active Presence
Notes To Developer
Apps must have an active presence in the Store. When determining active presence, Microsoft looks for factors including but not limited to: acquisitions rate, update frequency and adoption of new platform features/capabilities."
With other words: According to this your software can be removed by Windows Store, if it has no "enough" downloads, even when the software is bugs free, periodically updated, MS takes 30% for each acquisition, the membership and the OS are paid (the paid OS is necessary, because of the Containers feature, to can create the .appx package)!