To be honest, from an engineering standpoint I’m amazed whenever any of the doubletap smartapps that use precision timing works in a cloudbased system like SmartThings. The problem is that the round-trip time just varies a lot. This makes it extremely difficult to capture a true double tap on the switch.
Because i’m quadriparetic I don’t use this feature at all myself, so I don’t have any personal experience with it. From what I can tell from just reading the forums, it seems to break, regardless of the app or switch you’re using, pretty often. Which again I put down to different processing times because of the cloud architecture.
It would probably be best to start a separate topic in the smart app section of the forum and just ask if people are successfully using any double tap smartapps at this time. (Look for answers from people other than the author of a particular app to get a full picture.)
Meanwhile, as of April 2016, there is a new line of switches from homeseer which offers both double tap and triple tap functionality that should work well with SmartThings because it uses an entirely different method. Instead of trying to precisely time events that are sent through the cloud, the switch itself determines if it’s a double tap or triple tap and then sends a single code to the cloud. this removes most of the problems with lag.