I believe that there is a misconception about how IPs work here. When you use 127.0.0.1, you are using a very special IP that all NICs associated with the loopback interface (also known as localhost). Obviously, any other computer can't access your computer from by using the 127.0.0.1 IP, since every computer "thinks" that themselves are 127.0.0.1, and no other. Therefore, your colleagues' computers will reach himself by accessing the 127.0.0.1, and not you.
If your colleagues are in the same network as you, they could access using your private IP (execute
ipconfig on Windows or
ifconfig on Linux to find it).
To see your public IP, you can go to http://myip.bitnami.com/ in your browser. Probably you will need to make it accessible form internet. This link could be useful:
I hope it clarifies things.