Installing Pi-Apps is as simple as runing this one command in a terminal

wget -qO- https://raw.githubusercontent.com/Botspot/pi-apps/master/install | bash

To install manually if you prefer to see what happens under the hood

git clone https://github.com/Botspot/pi-apps && ~/pi-apps/install

To uninstall Pi-Apps you can use the built in uninstall script

~/pi-apps/uninstall