Startup Idea : Bathroom Stopwatch

I always take my cellphone when I go to the bathroom because I use it when I need to count minutes, whether I'm brushing my teeth, putting on scrubs, wearing facial or hair masks ...etc. I've always wanted some kind of stopwatch that would motivate me to wait the whole 10-15 minutes inside the bathroom!! I never get to handle counting inside the bathroom, it is utterly boring.