The following is a responsive bar chart which updates when your screen is resized. Test it out!
The reason for developing this was to try to create a good mobile view for loan/returns data in SETLS which is binned in fifteen minute intervals from the first loan of the day to the last. This is problematic though, because occasionally late night loans/returns are performed by admin staff, so the graph is completely skewed and the labels on the x-axis just don't work. D3.js has the capability to sort out the labels and binning of the data - rather than doing it from the Rails controller, I'm developing a pure d3 solution now. Tooltips not working here but blue is 'loan' and pink is a 'return'.
When you search a business in google - e.g. this you get an activity chart of 'popular times' to help you plan your visit. This data is based on user locations (apparently!) -- or "aggregated and anonymized data from users who have opted into Google Location History", so may not paint an accurate picture. However, the data in SETLS is based on real user activity.