Being tired can seriously hamper ones productivity and concentration. If you don't get enough sleep on a daily basis you are far more likely to have trouble focusing or accidentally fall asleep at an inopportune time. Going to sleep at a regular time each day can help avoid these problems but is often inconvenient for people with constantly changing schedules.
My solution to this issue is the Sleep Schedule app. The app will collect data from the user on how well rested they feel after various amounts of sleep. From there it can synthesize how much sleep they need to function on a regular basis. When given information about the users schedule for the upcoming day it can recommend when they should get to sleep to best be prepared. The idea is to have flexible times and give the user optimal suggestions as well as acceptable other times.
Getting enough sleep on a daily basis will help people to be more productive and function better in general.