Any capacitive stylus will work fine on Noteshelf. Capacitive stylus are simple and affordable stylus that works that work in any device that has a capacitive touch screen. It requires no battery and they are the cheapest in the market. Always remember to look for the "capacitive" label when you're thinking of buying a simple stylus.
However, if you prefer advanced features, like palm rejection and pressure sensitivity, Noteshelf supports the following stylus in this link.