Manjaro Linux is described as 'Manjaro is a user-friendly Linux distribution based on the independently developed Arch operating system. Within the Linux community, Arch itself is renowned for being an exceptionally fast, powerful, and lightweight distribution that provides access to the very latest cutting' and is a very popular Linux Distro in the os & utilities category. There are more than 100 alternatives to Manjaro Linux for a variety of platforms, including Linux, Self-Hosted, Mac, BSD and Windows apps. The best Manjaro Linux alternative is Linux Mint, which is both free and Open Source. Other great apps like Manjaro Linux are Debian, Ubuntu, Arch Linux and Fedora.
Both Manjaro and Raspbian run on the Raspberry Pi, so one could replace the other in that context. Raspbian is optimized for the Pi; Manjaro can take a little bit of work to get it right.