article_snippet.sent: The Sleep Cycle app tracks a user's sleep as they go through a cycle of sleep phases.
article_snippet.sent: The Sleep Cycle app uses the phone's accelerometer to identify phases by tracking movements in bed and wakes users up during users lightest sleep phase, using a pre-defined 30-minute alarm window.
article_snippet.sent: The Sleep Cycle app has more than two million active users and gathered data for the study between 1 June 2014 and 31 March this year from users aged 18 to 55 in 47 countries.
article_snippet.sent: The Sleep Cycle app (pictured) tracks a user's sleep, as they go through a cycle of sleep phases.
article_snippet.sent: The Sleep Cycle app ( has more than two million active users and gathered data for the study between 1 June 2014 and 31 March this year from 941,329 male and female users aged 18 to 55 in 47 countries .
highlights_snippet.sent: Data was taken from 941,300 male and female Sleep Cycle app users .
  