What is fastboot intended for?
Fastboot supports a rather limited set of actions. Its primary uses include:
- flashing images (complete device-firmware or separate partition images, but also radio-firmware)
- erase/wipe partitions
- boot a specific kernel
- lock/unlock the bootloader
What fastboot does not do
Don't mis-interpret its name to be a "fast alternative to boot your device" (unfortunately, some manufacturers like HTC and Sony have a similarly named "Fast Boot" option). Admitted, a start into fastboot mode is faster -- but that's due to the fact it only needs a limited set of libraries etc. It does e.g. not start Zygote or the System Server (see: Can somebody explain the boot process of an Android device? -- that's what above mentioned "Fast Boot" option on some devices does for a "fast boot": killing the System Server; Unix-Users might compare that to killing the X-Server), so no GUI and no apps here. Neither does it offer a full set of commands (shell access) or the like. As described, it's just a very minimal system for a very specific purpose.
Some good questions and answers tagged fastboot
- What does “fastboot oem lock” do?
- I can FastBoot my device. How can I reinstall an Android image to it?
- Unlock bootloader using fastboot using Ubuntu/Linux
Ever-returning Troubleshooting questions
- fastboot doesn't see device (Windows)
- ADB can discover devices but not fastboot (Linux)
- adb can find device but fastboot cannot (Linux)