I wanted something to check log file (20GB+) output, this is the only app I have found that can do it without delay, I can just keep clicking the "Tail" button to see that latest rows added to the file i.e. updates dynamically.

Speed is unbeatable. If you want to see the end (or start) of a huge text file (e.g. log file) in an instant and search within that then I haven't found anything better. Got it in the Windows Store, so installation is easy.