The hardening checklists are based on the comprehensive checklists produced by CIS. The Information Security Office has distilled the CIS benchmark down to the most critical steps for your devices, with a particular focus on configuration issues that are unique to the computing environment at The University of Texas at Austin.

HOW TO READ THE CHECKLISTS

Step – The step number in the procedure. If there is a UT Note for this step, the note number corresponds to the step number.
Check (√) – This is for administrators to check off when she/he completes this portion.
To Do – Basic instructions on what to do to harden the respective system.
CIS – Reference number in The Center for Internet Security (CIS) benchmarks. The CIS documents outline in much greater detail how to complete each step.
UT Note – The notes at the bottom of the pages provide additional detail about the step for the university computing environment.
Cat I – For systems that include category I data, required steps are denoted with the ! symbol. All steps are recommended.
Cat II/III – For systems that include category II or III data, all steps are recommended, and some are required (denoted by the !).

Please follow hardening step and make your android devices more secure.

https://security.utexas.edu/handheld-hardening-checklists/android