Recon
Lessons filed under Recon.
Recon The phases of a security assessment Learn the order that security work happens in, and run the first steps on your own phone.
Recon Taking inventory of your own devices Build a plain list of what your own device has, with commands that need no root.
Recon Reading a port scan properly Run nmap against your own phone and learn what each line of the output is telling you.
Recon Service versions and what they tell you Ask an open port what service and version is behind it, and read the banner it sends back.
Recon Finding and judging a vulnerability Turn a version string into a decision, without overreacting to every old number you find.