What is a9lh?

a9lh, or arm9loaderhax, is a custom boot loader for the Nintendo 3DS handheld gaming console developed by Plailect. It allows users to install custom firmware, known as CFW, which grants them more control and access to the system's software. a9lh also enables users to install homebrew software, use cheats, and backup their game saves. Additionally, it provides greater protection against system updates and Nintendo's anti-piracy measures. However, a9lh can be risky if not installed correctly and can potentially brick the device. It has also been largely replaced by a newer custom firmware called boot9strap.