Here's what you have to sell users on: Is it worth paying 99 cents to install a new app (that fits somewhere in their app list) just to get someone's location? How often when you text someone do you need their location, and is it enough to create the habit of using this?

Keep in mind that many location-based questions don't require geocoding. Like, we've agreed to meet at Joe's Bar and I want to know if they're there or still eating dinner at the restaurant...I don't need to see it on a map.

Moreover, the user receiving this message will have to trust this new site they've never heard about. some users will click through but there will be plenty of users who have been twitter-phished and be inherently distrustful. The sender can put in more effort into the message, i.e. "Hey, this is Jon, I'm using this app to geolocate you so just click through" but by then, you've lost a bit of the convenience factor.