I\'m trying to install ngrok (which I\'ve been using for a while on Windows with no issues) on my 1 week old yosemite and these are the steps I\'ve followed so
ngrok
For installation in Windows : Download and extract to any directory (lets say c drive)
Then double click on the extracted ngrok.exe file and you'll be able to see the command prompt.
ngrok.exe
command prompt
And just type ngrok http 4040 // here I am exposing [port 4040]