I changed the data feed. I remember that I used this feed in 2 MashApps.
How can I find the referenced MashApp to a DataFeed?
I couldn't find references.
Another question. Is there a possibility to sort DataFeed to modification date. The creation date is not always helpful for me.
There is no way to list MashApps that use a given feed. One way is to manually inspect the data assignment dialog for each chart in your MashApp.
Alternatively you may export the MashApp in question and import it into a separate installation of MashZone. Since the export file contains every feed the MashApp depends on it will reveal the feeds.
I must admit, sort by modification date was helpful. The modification date is listed in the Data Feed/MashApp details.