In the Netherlands they have this Nutri score label on products.
That only gives an average health score for a product based on sugar, fat, salt....

But the stupid thing about the label is that it represents a relative score compared to similar products. So a pizza could have an A because other pizza's have more fat and salt, but Greek Yoghurt with 10% fat can have a C.
The yoghurt isn't compared with the pizza, but with other yoghurts.

I'll try the app, thanks!