Since you look at yourself every day, subtle changes in your skin’s texture and appearance can be hard to detect, making it even more difficult to determine if your skincare routine is paying off. Enter: skin-analysis tools like the new Skin Diary feature on the YouCam Makeup app. With a quick selfie, the app indicates areas of your face with wrinkles, spots, texture, and dark circles

Now, I know what your first thought toward apps like this might be (because it was my first thought, too): Is this an app solely made to shame me and my dark circles? And yes, the idea of a phone pointing out every spot on your face can certainly be a turnoff, but when you use it to track your skin’s health compared with a week or a month ago, the concept is intriguing — especially if you’re a skincare junkie like me.

For the best results, the app suggests taking daily selfies in the same location and with the same lighting to track your skin for that day. (This part is key! I tried it under different lighting all within five minutes and was told my skin age ranged anywhere from 23 to 29 years old.) The numbers, or “scores,” you receive represent your skin’s health compared with YouCam’s database of other people’s faces. The higher your score in each of the four categories, the healthier your skin.

Check your scores and your skin’s progress over the course of a few weeks or months to see, once and for all, if all those pricey products and treatments are really worth it. Or, you know, just have fun playing around with the skin age feature, which is more addictive than any phone game I’ve ever played.

YouCam Makeup, free to download on the App Store and Google Play.