Google announced "property sets” that let webmasters combine multiple properties (sites as well as apps) in a group to monitor overall clicks and impressions in search in a single report.
You can get started in four simple steps:
1. Create a property set
2. Add the properties you're interested in
3. The data will start being collected within a few days
4. Profit from the new insights in Search Analytics!
Google said, “This feature will work for any kind of property in Search Console. Use it to gain an overview of your international websites, of mixed HTTP / HTTPS sites, of different departments or brands that run separate websites, or monitor the Search Analytics of all your apps together: all of that's possible with this feature.”