Smoothly visualize and measure the current acceleration in real-time. It can be used on earth, on moon or in orbit (where relative would be equal to absolute mode – please prove) to visualize the direction and strength of the gravitation – or simply at home to measure the g-forces you reach while shaking your phone – however be warned if you tend to get to the limits! . A fun application is to place the iPhone/iPod steady in your car (or any other moving vehicle), go to relative mode, zero it once when you are standing and then see the current g-forces in effect while you drive (e.g. what g-force does your car reach when you accelerate?).
User Manual
The red buttons switches between the two main modes (Acceleration and Acceleration-Relative). The yellow button function depends on the main mode (4 sub-modes for Acceleration and Reset in Relative Mode).
Acceleration Main Mode
In this main mode the yellow button switches between the following sub-modes.
Absolute Mode (Initial): Displays the reverse acceleration of the iPhone (1g up when hold steady). The digital indicator shows the acceleration in g. We will add the option to reverse this arrow in this mode with the next update of this software.
Z-Rotation: The arrow will display the rotation around the Z-Axis of the iPhone. The digital indicator shows the angle numerically (-180° – +180°) where 0° is in the center. A way to calibrate will be added with one of the next updates, so you could use this as a level.
Y-Rotation: The arrow will display the rotation around the Y-Axis of the iPhone. The digital indicator shows the angle numerically (-180° – +180°) where 0° is in the center. A way to calibrate will be added with one of the next updates, so you could use this as a level.
X-Rotation: The arrow will display the rotation around the X-Axis of the iPhone. The digital indicator shows the angle numerically (-180° – +180°) where 0° is in the center. A way to calibrate will be added with one of the next updates, so you could use this as a level.
Acceleration Relative Main Mode
In this mode the yellow button resets the compensation vector.
Relative Mode: This mode shows the relative strength (absolute minus compensation vector) of the acceleration. When the device is rotated in any direction the compensation vector has to be reset by pressing the yellow button when holding steady.
Final notes
To use as a metal detector the objects need to be actively magnetic since physically no strong enough oscillation is actively produced on a typical mobile device (not specifically built for this application). This is fundamental.
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) and each magnetometer usually recalibrates internally when over ±120μT in one axis. However, tell us your experience!
I am a physics teacher. I use this app to help my students to develop a more intuitive understanding of acceleration. I ask them to hold it level in their laps while riding in a car. This is quite helpful. It would be better if it could be made more sensitive. If you try it yourself, you will know exactly what I mean. If this were just a little better set up for this task, every physics teacher in the country would have every one of their students download this app.