I have a custom field "Time to Finish" in my custom content type in Drupal7. The "Time to Finish" is basically a timer of sorts. whenever the users click a flag (which is placed on nodes of that custom content type) the timer should start. The difficulty associated with this is that:

1. Every node of that content type has different Time to Finish
2. The timer should start on flag click (the flag is same on all node, "Start Flag")
3. Every user would have their own timer then depending on when they click on the Start Flag

The admin while creating the content should have the option to fill in the field "Time to Finish" and on flag click the timer should start. Any suggestions. Would really appreciate it.

Thanks

PS: As of now "Time to Finish" is of type Date.