CampiLevel

CampiLevel supports the alignment of the caravan/camper.
For this the iPhone is simply placed on a flat place in the caravan which should serve as a reference for the alignment.
The respective inclination for the longitudinal and lateral alignment is displayed in degrees and additionally the necessary underlay of the "hanging" side in mm which is necessary to compensate the inclination.

Furthermore, if available, the app on the AppleWatch is provided with the same information. 
So you can use the AppleWatch, even as the driver of the towing vehicle, to check the alignment when manoeuvring.
A speech output with adjustable volume helps to correct the steering instead of always looking at the display.

Furthermore, a compass is displayed to quickly check in which direction, for example, the entrance points.