Sleep Cycle - Bio-alarm clock that wakes you up at optimal times based on your sleep patterns.
Timer Tab - Online countdown timer, alarm clock, and stopwatch.
SleepBot - SleepBot is a sleep tracking app available in Google Play and the Apple App Store.
Gestimer - For those little reminders during the day
Online Alarm Clock - The world's original online alarm clock, established in 2006.
Online Stopwatch - Online Stopwatch is free to use online tool that allows you to keep track of the important events and tasks that you are performing.