Does anyone else find it hard to work out what ingredients are causing allergies?

I have really sensitive eyes - some products work for me and some don't, and I've never been able to work out what ingredient(s) are causing the reactions. For example, hypoallergenic brands like Clinique and Laura Mercier are usually okay, but not always, so I can't rely on it. I feel like I've wasted so much money on products that I think will be okay, but end up causing trouble.

Is there an existing way to work out exactly what ingredients I am reacting to? I was wondering if there would be any merit in building an app where users could log products that cause issue, and it could identify the common ingredients. Would this be something people would use, or is there a way you are already working it out?