Pinch - iMessenger HD’s big selling point is it allows free texting over Wi-Fi and 3G Internet connections. But it does a lot more than that.

The 99-cent social networking app is much more like a combination of a texting and instant messaging service, combined with a geotagging service like Foursquare. From Pinch, you can send texts and emails, and make phone calls to anyone in your address book. The former two go out on your iPhone’s 3G Internet connection, so they don’t actually count toward your texting service plan.

Pinch gets cool when it combines social networking services with regular phone services. If you have friends on Pinch, you can send geotagged updates to one another (like Twitter). Pinch allows you to identify friends on Google Maps, showing where you are in relationship to people on your contacts list.Then, you can tell it to direct you so you can get to your friends; and while you’re on the way, send IM-style texts that include emoticons and animations.

Pinch also allows check-ins to different locations. Checking in and using Pinch, inviting other people to use it, and doing other activities in-app earn you points that can be applied to raffles and sweepstakes, in which you could win various prizes. It’s unlikely to pay off for most users, but the possibility of getting something back just for interacting with friends is a welcome treat in a service such as this one.

The one drawback of Pinch is that most of the coolest features require other people to have the app. It’s available on multiple platforms and only costs 99 cents, but it still means you need to be a Pinch pitcher if you want to get the most out of this cool app.