 In real time, after you connect it to your iPhone or your Bluetooth device, it will show you exactly what you're doing and how to correct it. It's really easy to use. The Marines have been using this. Now it's used military-wide. It's MantisX, M-A-N-T-I-S-X, MantisX.com. Go there now and increase your competency with confidence. Today, MantisX.com. Ten seconds, station ID.