A secondary operation, unlocking the device's bootloader verification, is required to remove or replace the installed operating system. Rooting is required for more advanced and potentially dangerous operations including modifying or deleting system files, removing pre-installed applications, and low-level access to the hardware itself (rebooting, controlling status lights, or recalibrating touch inputs.) A typical rooting installation also installs the Superuser application, which supervises applications that are granted root or superuser rights by requesting approval from the user before granting said permissions. Rooting lets all user-installed applications run privileged commands typically unavailable to the devices in the stock configuration. The former allows removing the SIM card lock on a phone, while the latter allows rewriting the phone's boot partition (for example, to install or replace the operating system).

Rooting is distinct from SIM unlocking and bootloader unlocking.

Thus, it is primarily the third aspect of iOS jailbreaking (giving users administrative privileges) that most directly correlates to Android rooting. Similarly, the ability to sideload applications is typically permissible on Android devices without root permissions. Many vendors such as HTC, Sony, OnePlus, Asus, Xiaomi, and Google explicitly provide the ability to unlock devices, and even replace the operating system entirely. However, these are different concepts: Jailbreaking is the bypass of several types of Apple prohibitions for the end user, including modifying the operating system (enforced by a 'locked bootloader'), installing non-officially approved (not available on the App Store) applications via sideloading, and granting the user elevated administration-level privileges (rooting). Root access is sometimes compared to jailbreaking devices running the Apple iOS operating system. On some devices, rooting can also facilitate the complete removal and replacement of the device's operating system, usually with a more recent release of its current operating system. Thus, rooting gives the ability (or permission) to alter or replace system applications and settings, run specialized applications ('apps') that require administrator-level permissions, or perform other operations that are otherwise inaccessible to a normal Android user. Rooting is often performed to overcome limitations that carriers and hardware manufacturers put on some devices. Because Android is based on a modified version of the Linux kernel, rooting an Android device gives similar access to administrative ( superuser) permissions as on Linux or any other Unix-like operating system such as FreeBSD or macOS. Rooting is the process by which users of Android devices can attain privileged control (known as root access) over various subsystems of the device, usually smartphones. Not to be confused with bootloader unlocking or SIM unlocking.

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