Samsung Knox, Asus Zenfone, and any device with SELinux Enforcing (change to Permissive if possible via an app like SELinuxModeChanger – ironic because that requires root first).

Rooting Android 5.1.1 (Lollipop) without a computer is typically achieved using "one-click" rooting applications. These apps exploit specific vulnerabilities in older Android versions to gain superuser access directly on the device.

KingoRoot is often considered the most successful tool for Lollipop devices. It uses a cloud-based database of exploits to find a path to root access.

There is always a risk that the process fails, leaving your device stuck in a boot loop or completely unresponsive.

: Use the Bugjaeger app on the second phone to send fastboot commands to the Android 5.1.1 device, allowing you to flash a custom recovery like TWRP or a patched boot image. Critical Safety & Risks