Bluetooth for tooths

I'm a pretty late adopter of electric toothbrushes.   I started using one, the base Oral B model, maybe 3 or 4 years ago?, and that was only because my daughter didn't like using it at that time.  

That one's battery performance finally deteriorated enough to get a new one on the weekend, and I was surprised to learn that for only $99 I could buy an Oral B model with Bluetooth connectivity.  It apparently tells an app on your phone about how well you are brushing.

This seems faintly ridiculous to me.   (As indeed does that way Oral B seems to flood the market - which I assume it already dominates - with seemingly 12 different models, many with very small differences.  It's a bit like how some mobile phone companies operate.)  I don't want my brush reporting on me to my phone, or indeed, the head office.   

Anyway, I went with what's probably only one model up in sophistication from the very base model.  Now I not only have a 2 minute timer (which had stopped working on the old one), but every 30 seconds it stutters to tell me that I have spent enough time on that quadrant of my teeth, and I need to move onto the next quadrant.  I actually like the 30 second feature.

Electric toothbrushes do feel like they have given teeth a thorough clean, and I see that research into the comparison with manual teeth-brushing backs up the impression.  

I would prefer that the brush heads were cheaper, but can't have everything...