Is there an app that will drain my battery? Are there any apps that will specifically help to drain a battery down quickly?

The scenario I would want to have this is if I want to quickly drain the battery so I can charge it fully again.  Some say that this will help extend the battery life by fully draining/charging the battery.
Do not do this. You are actually harming the lifespan of your battery when fully discharging it before a recharge. See this site for a discussion of how depth of discharge affects battery life.

The only reason you might want to fully discharge before a recharge is if you have a NiCad battery that is susceptible to the memory effect. Your smartphone most likely uses a Lithium-ion polymer battery, so there is no good reason for you to totally discharge your battery. The lifetime is longer if you have a shallow depth of discharge.