Introget good marks
For have More time to study other subject
Body against bad habit
On the one hand, it is evident that in today´s world It can Help you to get good marks.In addition,they have more Time to study other subject.
On the other, there are many arguments that can besaid against They can bad habit.
To conclude, there is much to be said on both sides of the Topic, but in my opinión they are good but if they are used in a right way.