Alternatively, you can use a pen with its cap on (if you have a screen protector it should be fine). If not, those cotton thingies to clean your ears should be good, too.
You are in the US, right? $4 can't be too far out of the question if you are. Take back some bottles or something. Mow a lawn. Rob an old lady. $4 is pocket change these days. It'll only buy you three candy bars.