Q1: What does su do? What is a significant thing that su allows you to do that you can’t do otherwise?

The su command grants root access on the Android machine, allowing full control of the system. This enables actions such as accessing protected directories like /data/data, where app data and user information are stored, bypassing file access restrictions, directly examining system logs, etc…

Q2: What is /dev used for in Linux?

/dev is a directory in Linux that contains device files, which represent hardware devices like disks, USBs, and virtual devices. These files allow user space applications to interact with hardware.

Q3: In what partition are app APKs stored, and where is this partition mounted onto the filesystem?

App APKs are stored in the /data partition, specifically in the directory /data/app. This partition is mounted as /dev/block/dm-32.

Q4: In what filesystem (partition) do apps typically store sqlite databases?

SQLite databases for apps are stored in the /data/data/<app-package-name>/databases/ directory. This directory is part of the /data partition, which is mounted as /dev/block/dm-32.

Q5: Where is the SD-card mounted?

The SD card is mounted in the /mnt/sdcard directory, which is part of the /dev/fuse filesystem.

Q6: What is the largest mounted partition in the emulator (excluding the SD-card)? What is the /dev name of this partition?

The largest mounted partition is /data (5.8G), and the /dev name of this partition is /dev/block/dm-32.

Q7: Can you create files in /system? Why / why not?

You cannot create files in /system because it is mounted as a read-only file system by default, to protect system integrity.