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
If you downloaded via a download link, you need to add ngrok path to your .bash_profile or .bashrc whichever one you are using.
For Windows 10 bash:
Download ngrok from https://bin.equinox.io/c/4VmDzA7iaHb/ngrok-stable-windows-amd64.zip
Move executable file ngrok.exe to C:\Windows\system32\ngrok.exe
Add Environment Variables via UI (search for "Edit the environment variables for your account" in the search bar next to windows logo => double click on Path under Users Variables for yourusername => Click New => add your path C:\Windows\system32\ngrok.exe => click OK.
Restart your bash and you should be able to run "ngrok http 80" command.