what g-force does your car get when you accelerate?). The application has five different display modes for acceleration visualization: - Absolute Mode: Displays the reverse acceleration of the iPhone (1g up when hold steady). - X-Rotation - Y-Rotation - Z-Rotation: The arrow will display the rotation around the X-, Y- and Z-Axis of the iPhone. The digital indicator shows the angle numerically (-180° - +180°). A way to calibrate will be added with one of the next updates, so you could use this as a level. - Relative Mode: This mode shows the relative strength (absolute minus compensation vector) of the acceleration. For a detailed documentation, please visit our product homepage. For recreational use only. However it CAN (!) be very accurate. The measurement is performed as good as possible (we try our best) by using the inbuilt accelerometer and magnetometer to their limits. The range of the accelerometer typically has a max of ±3g (~4.2g displayed here if combined). However, tell us your experience! Check out all our products (free and paid) on www.plaincode.com