The Tap isn’t supported by the Cloud version of the Hue app, it only supports lights and power plugs.
@TimTheToolman the reason is that switches are input devices, which require polling (the app needs to actively “ask” the Hue hub, through its API, if a switch has been pressed). This takes up a lot of bandwidth (historically, the Hue app has been known to cause massive amounts of data transfers on “regular” Homey’s) and I guess Athom doesn’t want to be paying for that.