The main piece of equipment you need for this to work is a USB OTG cable/adapter. You can plug most USB peripherals (like keyboard, mouse, hub, etc) without issue using this.
However, dependent on the stick, there may be limits. I think the highest I've heard is 32GB USB2.0. Anything higher or requiring USB3.0 may not work due to greater power requirements required to operate. USB external HDDs work but require an external power source. A powered USB hub may overcome these restrictions, but will be dependent on the make and power it provides.