Is there any nice way to make a quick auto performance check to decide the quality of the graphics to use on the device your game is running on

I'm making a game for children on android. It suppose to decide it self which quality graphics to use depending on the device. For the moment to decide I check the frame rate of the first scene of the game how ever since the first scene of the game is not really representative of the performance needed I have to add extra invisible graphics. This method doesn't' seem like the best at all and I would like a cleaner better method if possible.If any one know of something of unity helpful for this task it would be nice. thanks in advance for any help.