I don't really understand how this is news - this is no different than when I spend an hour browsing #antiquewatch and then switch to #denverbroncos and end up

I don't really understand how this is news - this is no different than when I spend an hour browsing #antiquewatch and then switch to #denverbroncos and end up on #startups. The same thing happens if you share a netflix account - I had a good laugh with my partner when I started getting barbie movie recommendations. That doesn't mean Instagram isn't able to track the activity specific to each device though. Just like if you are logged into 5 Instagram accounts on one device they're probably attributing activity to both the active account AND the device.