It’s your first time in this city, and as you reach the center your iPhone makes a little chirp. There’s a message for you.
“Welcome! You finally made it here.” it says. “Just between you and me, that cafe right in front of you serves bad, overpriced coffee. Walk two blocks east and you’ll find a much better one. Love, Mom.”
Wait, what? How does your mom know you’re even here?
She doesn’t. But Dropp does.
Dropp lets you leave location-based messages anywhere, ready for other Dropp users to pick up next time they pass by.
The messages you drop can be text, or photos. They can be public, viewable by all – or private, only seen by your friends and loved ones.
What’s the downside? Well, it’s Yet Another Social Network to sign up for. Yet another username and password.
But the upside is that you can leave messages for people pretty much anywhere you take your phone, and where they are likely to take their phones.
Leave your loved one a surprise under the pillow. Leave your boss something suitable in the meeting room. Tell the barrista at your local coffee shop how much you appreciate her. Warn tourists visiting your city about the places that will rip them off.
The world is, as they say, your oyster. But now it’s an oyster you can stick hidden virtual messages to. Go crazy.
More on TIME.com:
AT&T Sells Tiny GPS Tracker with Mobile Alert Service
Verizon to Slap Phones With Location-Tracking Disclaimers
Class Action Suit Filed Against Apple over Location Tracking