Thanks for updating the documentation!
Querying device history in conjunction with htmlTile allows for very cool stuff - I managed to show today’s energy production overlaid with yesterday’s data for my solar array (custom device type) using Google Charts:
(Note that this is not an image but rather a dynamically created chart).
I still need to do some cleanup (both code and visual - the graph size needs to be improved) but will post the code when I’m done.