Just found this online at the app store and it looks pretty cool. Its an inclinometer for your android phone or iphone. its called 4x4 app inclinometer. You can even pick out a picture of a defender landrover, range rover or a landrover disco 4, I know its not a disco 1 or 2 but it'll do!! ... its better than a pic of a jeep.

 

Yup, I've got one too. Works pretty well.

 

There are free ones too.

 

Yeah I know, but this one actually has a pic of land rovers.