I am quite obsessed with the quantified self concept and productivity. I really like to get weekly stats on the use of my time, and gaining some insights on how I spend it:
There is no shortage of apps to track time, such as Toggl, Rescue Time, spreadsheets, etc. However, I ended up tracking my time with Google Calendar, specially because it allows me to drag&drop activities, and there is no duplication in logging them (I already put most of them in the calendar. Nevertheless, when using any other tracking app, I needed to insert them in the app too).
While there are some time-tracking apps that offer some kind of import from Google Calendar (e.g., Timeneye, they do not really suit my use case, where I have a calendar per life area/project, color coded activities without dependency on their names, etc.
Because of this, and as a learning web project (Django back-end + front-end), I will create my own web dashboard with statistics from Google Calendar.