How does this compare to tools like Charles and BurpSuite?

I've used Charles extensively in the past for this sort of testing, and particularly on mobile apps (it's not clear if/how mobile apps are supported with this).

Edit: Ah, "Now you just need to replace the original endpoint with interceptor’s URL inside the app." – so it sounds like this is basically a proxy at the HTTP level in the target app, rather than a network traffic interceptor at the network level on the system.