Time Insight allows you to easily track where your time is going. The database is your Google Calendar. To enter the data, you can manually add hashtags ("#meeting", "#email") to appointments in the past and in the future. You can modify their duration to match reality. Moreover, the add-on provides a punch clock with a "Start" and "Stop" button to quickly and precisely create the appointments on the go. You can use all the power of Google Sheets to create multiple views with the right time and project granularity. For example, you can just show the current day, month or year, and sum per day, week and month. You can group together several tags in one coarse view, but keep them separate in another view, to understand the details.