I have a time string, the first user's last login : '2014.12.01, 12:25' And how to calculate the time different from now? For e.g. another user see the first user's last login
At 12:30 and it says 5 minute ago.
Or at 13:23 says 48 minute ago.
Or at 14:24 says 1 hour ago.
Or one day later, it says 1 day ago.