The most impressed error that I found is an error in a famous App called 'echo',which is a popular music player,people can search the song they want to listen to and they can download that song at the cost of sharing that song with the friends from the wechat or qq or micro blog or any other socialization App. But just right now I found that if I don't click the 'download' button but share it firstly in my wechat, then if I wanna to download it, I have to share it again. It's weird because we compeletely don't need to share twice or more, what we need is whenever we dpwnload the song, if we have shared it before, we can just download it without sharing.
Obviously, the impact is so big, it will lose its customers because they don't want to share one specific song again and again. I supppose it is a impressed error for me and I hope someone can fix it as soon as possible.