Tow-Boot is not an app. It is an open-source —the first piece of software that runs when you press the power button. Its job is to wake up your hardware, initialize the RAM and storage, and then load your operating system (like postmarketOS, Ubuntu Touch, or a specialized Linux distro).
: Some distributions that use Tow-Boot (like postmarketOS) are based on Alpine Linux, which uses the .apk extension for its system packages. A "Tow-Boot apk" in this context would be a package containing the bootloader binaries or flashing utilities for Alpine-based systems.
By holding a specific key combination at startup, Tow-Boot turns your device into a USB flash drive. You can plug it into a computer and flash an operating system directly to the internal storage (eMPMC).
This is an incredibly popular, opinionated distribution of the U-Boot bootloader . It is famously used on devices like the and Pinebook Pro to make booting simple and standard.
For the vast majority of Android users, the tools you're looking for will be found in the conventional Android ecosystem of bootloader unlock APKs and fastboot commands. For those on the bleeding edge of mobile Linux, however, Tow-Boot represents a significant step toward a more standardized, user-friendly, and "boring" boot process—which, in the world of bootloaders, is the highest possible praise. It's not an APK, but for its intended audience, it's the most elegant solution yet.
Understanding the difference between a bootloader and an Android app.
However, there are two distinct technical projects named "Tow-Boot", and neither of them uses a standard Android APK file.
By offering a standardized UEFI/ACPI environment, it reduces the need for "downstream" kernels (heavily modified vendor kernels) and encourages the use of "mainline" Linux kernels. Conclusion
Create a feature to "Automatically boot from USB if SD card is present."
However, based on your request, you likely want to achieve one of the following:
First, let's break down the terminology.
Tow-Boot decouples the firmware from the operating system. It installs to a dedicated protected area of your device's storage. Once installed, it presents a standardized UEFI interface. This allows you to download a generic Linux distribution image, flash it to an SD card, and boot it instantly—exactly like plugging a bootable USB drive into a laptop. Key Features of Tow-Boot
is not an Android application (APK); it is a system firmware/bootloader (similar to U-Boot or EDK2/UEFI) that runs on the hardware "bare metal" before the operating system starts. Therefore, you cannot "install" Tow-Boot via an APK file.
However, if you are a developer working with embedded Linux systems, using or planning to use a Linux smartphone, or exploring ARM SBCs, Tow-Boot offers an incredible advantage. It creates a universal bootloader that solves a major fragmentation problem in the ARM Linux world, allowing you to move an OS image from one supported board to another without changing the bootloader.