> the messaging application, not being able to observe that the user is still interacting with their device, may assume that they have left to grab a coffee and

> the messaging application, not being able to observe that the user is still interacting with their device, may assume that they have left to grab a coffee and start delivering notifications to their phone, causing it to buzz distractingly, instead of displaying notifications on their desktop or incrementing a badge count. Is any webapp doing this? To me it sounds like multiple steps into the future: - First a webapp has to have the capability to notify just one device, so in this case your browser and not also your phone. I cant think of an app where you dont receive double notifications on web+mobile (or triple with a smartwatch). - The webapp then needs to be smart enough to dynamically select the "most active" device to send the notification to. - The new feature can then be used as a workaround for "incorrectly" classifying your computer as an inactive device, because you are not interacting with the webpage anymore.