Hello @TITAN,
the sample application you use just shows live data.
All incoming messages are just drawn on the page, there is no historical storage.
You can try to change the code so messages are both put in some kind of storage and pages get live data. Once a page is opened/refreshed, the latest historical data (last x hours of messages) is gathered and represented. After that, the newest messages are added to it.
You can also check out more conventional ways to represent data like Grafana.
Also, check out PowerBI in the cloud. It has a convenient built-in temporary storage accessible using Azure Stream Analytics.
Either way, you need to think of adding an extra step between receiving incoming data and (temporarily) persisting historical (warm path) data before you represent it.
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