This is a simple Facebook Messenger Webhook, which allows you to receive and send messenges.

1. Use tutorials to get API key:
   • russian
   • english
2. Create heroku account and create app there.
3. Go to Settings section and add Config Vars pair: PAGE_ACCESS_TOKEN and token you got via first step.
4. Add another pair: VERIFY_TOKEN and any value you want.
5. Go to Deploy section and deploy that bot

Now click on open app button and you would get "Hello world" page.

If you not, use heroku logs to find bug.