The Shodan tool, commonly known as the hacker's search engine, also comes in a mobile version for NetHunter users. Use of the Shodan app also requires an API key, which you have already been assigned if you signed up for an account in Chapter 4, Footprinting and Information Gathering. Visit http://www.shodan.io and log in (or sign up) to view your API key at the top-right corner of the browser. Enter the API key into the Shodan app on your mobile device when prompted.

Once you've acquired and entered your code, you can use the Shodan app in the very same manner as you would within a browser: