The onRecordEvent block in the Data section is no longer supported in App Lab. Projects that use this block will encounter the following error:

  ERROR: Line: 1: It looks like you're trying to use the onRecordEvent function.
  This function is no longer available. Try using the available data blocks.

If you would like to get your project working again, you'll need use a different Data block like readRecords

Why are we making this change?

The onRecordEvent block allowed App Lab projects to update immediately whenever a record changed. For instance, when two people have the same App Lab project running, changes either person make to records would trigger this event for the other person. While this enabled a number of powerful applications, the cost of supporting this capability has proven to be too great for us to support. 

We did an analysis of projects students have created with this block and found that a very small percentage of projects use this block. As such, we decided we needed to turn off the feature in order to focus our time and budget to other areas of our labs.