If you happened to catch my post last year about the release of the new Apex Realtime Debugger, then you might also be interested in checking out this demo recording which was made at the recent TrailheaDX conference last month.
The short talk was given by Greg Wester and if you are really just interested in seeing a good demo of the Realtime Debugger, then I suggest you skip the first 5 minutes of the 16 minute recording.
Greg also reveals at the end certain FAQ’s that you might be interested in which include:
- The Debugger only works in the Sandbox and there are no plans to ever have it work in production.
- Licenses are assigned via permission sets and you can only have one instance running per org.
- It does not support asynchronous code. Only synchronous operations.
- You can get a trial of the debugger if you contact your Account Exec.
- This fall they will be doing a pilot with vendors that allows them to step through managed code. This should be of big interest to ISV’s out there.
saramorgan.net 
Thanks for sharing Sara! I do think his points about “leased line” at the 2:40 – 4:00 minute mark is worth pointing out as until now I hadn’t realized why this debugging feature was paid $$. He does a good job, at least for me, explaining that to do real-time debugging requires that a sliver of Salesforce processing has to be peeled off and capable of being slowed down to allow say a 10 minute debugging session for an operation that might have normally taken 10 milliseconds. And considering this is a multi-tenant environment, this kind of power can’t be thrown around unfettered else havoc would ensue.
Just to throw this out there, if Salesforce’s Real-Time Debugger is out of reach for a customer then they might consider The Welkin Suite’s Retrospective Debugger which allows the developer to step through code, set breakpoints, etc. within the IDE after debug logs have been collected. Not real time, but also not really expensive either.
https://welkinsuite.com/the-release-of-the-apex-retrospective-debugger-in-the-welkin-suite-0-27-5/
https://welkinsuite.com/debugging-options/
Very good point Doug. Thanks for pointing all that out!!!