I have multiple offices and need to page all desk phones in various offices or departments but I don't want to page the mobile apps. It'd be much easier to define a page group by subnet. This would make it easier to send announcements or emergency alerts. It'd also (at least in my environment) exclude the mobile apps from the page group. Including/excluding the apps should should probably be added as a checkbox in the basic page group. A user could have the mobile app and a desk phone but I doubt I'd ever want the app to ring when paging. Currently it just wakes and rings the app but doesn't connect or activate the speaker phone.