[slow]

I use the Anderson Levelers and a 9" bubble level on the floor in the front baggage compartment. But I am totally dependent on the instructions I get from my DW while rolling the trailer until level side to side.

Recently, I loaded my phone with an iPhone App called Clinometer from the company "plaincode" that audibly calls out the angle of the phone over Bluetooth. I have not tried it out yet with the trailer, but it seems to be responsive enough if I used it as the level, that it has a chance of working so I can level the trailer without the DW's help.