Which criterion did this sleep cycle alarm clock fail to meet?
Humans sleep in cycles, usually two or three cycles per
night. There is a point in each cycle when waking up will
leave the sleeper feeling the most rested and refreshed.
After learning about this, a computer programmer
designed a new smartphone alarm clock. This new
alarm clock uses sensors in the smartphone to detect
the sleeper's motion and determine when the sleeper
has reached the best point in the sleep cycle at which to
wake up. The app can be downloaded onto any
smartphone. Most users who download this app find that
it does not help them wake up feeling more refreshed,
but they are willing to try improved products in the future.
It did not solve the problem.
It was not cost effective enough.
It was not readily available.
It was not safe for most users.