att-eptt-attAt&t has announced a new iPhone push-to-talk app for the business world. It is known as Enhanced Push-To-Talk (EPTT) and it’ll allow users to do PTT with one person as a private call or you can PTT with a group of people. The app supports up to 250 people.

The Enhanced Push-To-Talk uses Voice Over IP (VoIP) technology and can be used over Wi-Fi or At&t’s 3G or 4G networks. It currently supports the iPhone 4S or iPhone 5 only and requires activation.

The app itself is a free download, but the service is $5.00/month as an add-on to an existing voice and data plan or $30.00/month as a standalone push-to-talk-only plan.