Can I replace Android with Linux on a Galaxy Note 20 Ultra?

Android already uses the Linux kernel, but it isn’t the same as installing a normal desktop distribution. If you mainly want a less Google- or Samsung-focused experience, a supported alternative Android system may be more realistic. For a Note 20, check whether an unofficial build exists for your exact model, and don’t rely on it as your primary phone because banking, camera, cellular, fingerprint, and other apps may stop working.

The first thing to check is whether your exact model can have its bootloader unlocked. Samsung’s regional and carrier variants differ a lot, and some cannot be unlocked at all. Even with an unlocked bootloader, you’d need a compatible recovery, kernel, device tree, and working drivers. Root access or a custom kernel alone doesn’t turn the phone into a supported Linux device, and installing an unofficial build can permanently break features or the whole phone.

You can experiment without replacing Android by running a Linux userspace through an Android app or container environment. That gives you a terminal and many Linux packages, but it won’t provide a fully independent operating system or necessarily give you access to all phone hardware. A simpler option is also to use a different launcher and disable unwanted Samsung or Google apps.

Phones aren’t as straightforward as laptops. Linux support has to be developed separately for each phone because the hardware descriptions, kernels, drivers, modem, cameras, fingerprint reader, and other components aren’t standardized. Projects such as Ubuntu Touch, Mobian, postmarketOS, and ARM versions of regular distributions support only selected devices, and the Galaxy Note 20 Ultra generally isn’t an easy target.