Both The Rover and The Signal are sort of road movies, though The Signal eventually turns into a sort of science fiction movie, and both of them end with sort of surprises, which in neither case is very satisfying.
The Rover features really unpleasant characters, with a couple exceptions in the supporting cast. The Signal starts with three pretty acceptable collegians, but after turning into science fiction pretty much abandons characterization, except for Laurence Fishburne as a pretty unattractive military scientist or something-- I'm not saying any more than that.
Both feature scenic views: The Rover with appropriately dusty, dirty roads through an abandoned desert in Australia, full of deserted towns and dilapidated buildings with a few refugees huddled away in back rooms, except for one interestingly elegant old lady in formerly-fashionable spotless white lace; The Signal has a lot of sci-fi scenes in a military laboratory building, but its outdoors is another desert, also thinly populated.
The acting is not notable in either case, though The Rover has that fascinating grandmother and Robert Pattinson's interesting interpretation of a mentally damaged person.
Generally, The Signal is a little better than The Rover because it has more of a plot, though nothing is particularly new or surprising, while The Rover is too much just a series of episodes along the road with a surprise revelation at the end.
But it's hard to think anybody would consider either one the best thing in town.