I have tried many time trackers before I started to use TMetric, but each of them has its own cons. TMetric combines user-frinedly interface and a wide range of useful functions and integrations. Integration with Asana was one of the essential points for me. Also I like that Tmetric has a mobile time tracking app, so you can keep tracking of your activity out of office too.
I use Redmine + TMetric to manage my working activity and keep tracking of working hours and I am fully satisfied with these tools. TMetric helps me to stay productive and reduce the waste of time. Tmetric provides me with detailed time and tasks reports