Bought this 2 months ago and my 4 yo son loves this toothbrush. The app is certainly motivates him to go and brush his teeth at start but now he just loves brushing his teeth because its so efficient. It has a timer and very easy to use. Battery last for 2 weeks and he brush 2x a day in average. We have been using a normal spin electric toothbrush before. But with this one I noticed his teeth are definitely a lot cleaner.