Reply to Reward charts: Love 'em or hate 'em:?

I use an app (ClassDojo) for my 6-year-old. There are different skills that have different point values (bigger skill, more points). And we have a list of rewards that she can “trade” points for. Right now, she’s at about 100 points and is trying to save for a bike which is 500 points. It’s super easy for us because I can always just pull out my phone to give her points and she enjoys working towards the point goals.