Or maybe just make your web apps less terrible?
If a person has paid extra to obtain the only mobile that doesn't run Google's operating system, perhaps that says something about the extent to which they don't want their apps to look and behave like Google's operating system? So maybe it would be sensible not to override their native scrolling behaviour with a thirty-minutes-and-done half-hearted Javascript emulation of the same thing, and not plaster your own fifth-rate navigation bar underneath their ordinary navigation bar if they're inattentive enough accidentally to open an AMP link?
If they have a desktop computer, maybe accept the gesture that means "scroll vertically" to scroll vertically, not zoom? If you want a gesture to zoom, why not use that platform's zoom gesture instead of ignoring it completely?
Google is the last company that should be listened to re: quality of user experience.