We often explore what interesting things can be found in data that changes through time, and we have published experiments with temporal data at the Mobile World Congress (MWC). We showed how CartoDB could be used to map traffic in Barcelona, which automatically updated every 15 minutes throughout the day. In another example, we compared credit card purchases in Barcelona during MWC to those over a similar period not during the event, highlighting the utility of showing multiple maps side-by-side. By allowing users to zoom and pan into areas of interest, these side-by-side maps provide valuable insights that are helping users build data dashboards to support their missions of creating smart cities.