Mobile phone compass calibration method

Baidu checked two methods;
First, we put the quilt on the bed and threw the cell phone hard to let it go in the air for more than three and a half weeks, turning around 720 °;
The second is to put the cell phone horizontally aside and wait for it to calibrate.

After my own tests,
The first one is tossing for a long time, and the compass is not turned green and ineffective;
In the second case, the compass is white first. After a long time, it turns red. Then, the body gradually becomes hot. I put it for half an hour, but it still has no effect.

Recently, due to a coincidence, the third method has been obtained, that is, the subscribe has a calibration method, and the research is good. It is said that the three axes should be converted, I was thinking that the sensor might be slow, but as long as it slowed down, the calibration may be successful.

The third method is as follows:
So first put the mobile phone flat, point the calibration compass, click the calibration, do as follows:

The first step is to flip to the left;
Step 2: flip forward;
The third step is counter-clockwise rotation.

The flip process must be slow, stable, and not swaying as much as possible. It is the same as the slow-motion playback of a movie, and you can turn around it and restore it to its original position.

After completing the three steps, a miracle occurred, and the compass turned green, prompting that the calibration was successful. There are two options: one is to calibrate the other side, and the other is to close.

We recommend that you click Close, press the back key, then open the keyboard, and then click Calibrate the compass. At this time, the screen displays a horizontal screen, and the animation on the screen also pushes the keyboard's host to flip,
At this time, perform the calibration according to the above three steps. After the prompt is successful, click Close to return.

Sorry, there is no image, but you can see the sample image on your mobile phone. It turns very fast and it turns very slowly during calibration.