Apple surfaces this in the new system service Airdrop, shown above. The demo uses photos, but Airdrop is part of the standard sharing panel that any app can use, and (without breaking the NDA) it looks like anything you can make into a file could be sent. So an app can include a ‘share this with friends’ that sends people in the room an app store link. Or a game level. Or in-game currency. Or a deep-link to content within an app. That makes app discovery work quite differently.
Airdrop, though, only works with people in the same room, and so has a different set of scaling problems. The leading social messaging apps all have hundreds of millions of users, and I’ve lost count of how many such services there are in total - I found over 50 on Google Play that had over 1m reported downloads, and there are dozens more. Pretty soon there’ll be more messaging apps than ad-tech companies - a new bubble is inflating. But there might be a fair bit of value for those that can turn themselves into distribution and discovery channels.
An interesting thought. Airdrop, like Airplay before it, should not be slept on.