How do I update zsh to the latest version (not Apple's default)?
I like to use Homebrew to install and manage the software on my Mac hence these instructions are brew specific.
First, check the zsh info
$ brew info zsh
Most likely you'll see Apple's version so let's install zsh from Homebrew
$ brew install zsh
Once that's completed you'll need to edit your shells file to add the new shell path
$ sudo vi /etc/shells
Scroll to the end of the file and add the following line
/usr/local/bin/zsh
After you save that edit you'll need to update the default shell
$ chsh -s /usr/local/bin/zsh
Zsh is now upgraded. I also recommend installing Oh My Zsh. The handy upgrade command once installed is below
$ upgrade_oh_my_zsh