Why doesn't GA track install sources?

Question

Google Analytics

Analytics does not track app install channels. A very large part of them - "not set". Because of what it can be?

Answer 1

Google analytics cannot 100% determine the install source.
If you want accurate statistics, use metrics or any paid solution mat, appsfyer, etc.
If you still don’t want to deal with other analytics systems for applications, check if tracking links are correctly formed and google analytics is integrated