1) When installing on BlackView it lags. Espacially if you block only some apps, kid cannot use phone at all - it lags and is very slow. 2) A lot of feature are missing to use this app. 3) Time of app usage often is calculated incorrectly. Sometimes app works in background, not sure how, but in these cases hours of app used is too high 4) It is good to be able to group apps by some categories, like, school apps or learning apps and games, so that you can block some category but allow another category. 5) And the last one - clever kids somehow can break this app... :( Time limits do not work.