Nope
Short battery life.
Won't work with the phone that I own.
Costs too much for what it provides.
Display almost certainly invisible in bright sunlight.
In these modern ecologically aware times shouldn't we strive to use more environmentally friendly tech?
Maybe someone could invent a timekeeping mechanism that worked mechanically.
I know this is a bit fanciful, but some bright researcher might be able to find a way to store potential energy, and gradually release it to drive some sort of mechanical display that shows the time of day.
There would have to be a way to recharge the potential energy, of course,
Perhaps brisk repetitive movement would be suitably familiar.