Where it came from. Since I have a lot non-constant events every day, it become a hell to manage all them with alarms or calendar.

Historically I used to use a timers for this. It is disposable by its nature and gives me to know how much time left to an event.

The only challenge in this approach is to set timer that will ring exactly at required time. Every time you need challenge your math skills and have enough agility to press "Start" button at right time. Mainly, this app solves this problem.

What is it. This is addition above any clock application supporting Timer API for Android. Actually all Clock applications do it. Timer Manager supports two modes "Timer for specific time period" and "Timer until specific time moment". Both in range of 24 hours and can be saved as preset for reuse.

Timer for specific time period. Just runs straightforward timer functionality and usually already included in standard clock apps. Useful for things like eggs boiling or take a nap in midst of a day.

Timer until specific time moment. This functionality guarantees that timer will ring at exact moment of a day. Useful for events that happen at exact moment of a day, but at random day and should be activated on demand.