Quite a while back – 2016 to be specific – Google introduced a new function for the Android operating system called App Preview Messaging. The initial availability for this feature was as part of their introduction of the Google Allo messaging client. Things have been fairly quiet with regard to App Preview Messaging since then, but recently some sources have spotted notifications from Google Photos popping up indicating Google is at the very least testing this feature for their video and photo gallery platform.
App Preview Messaging is part of an API in Google Play services that can be used to let recipients of a video or photo preview the item even though they may not have the native application used to send the item installed on their device. For the launch of Allo, this meant Allo users could send a photo or video to a recipient that was using a different messaging app and the recipient could view the received item without having Allo installed. This makes it easier to share information between users on different platforms while at the same time creating a potential hook to encourage new Allo uptake since an invitation was always present to view the content in Allo even if that meant going through the process of installing it first.
The same type of functionality appears to be getting a test in Google Photos as sources have reported getting notifications that an item in Google Photos has been shared with them from another user. One benefit for recipients is that they can view the content from within the notification or go and open the app. When content is first received in this manner, Android will let you know that you can control the settings for display of this content.
Sources indicate Google has a developer API for App Preview Messaging in the preview stage and that the company is in the process of opening up an early access program for select partners. Along with Allo and now Google Photos, there have been reports that Google Duo is also testing use of the new API. Expanding testing to third-party app developers is a good indication that Google may finally have the platform advanced far enough to start making significant use of it.