Had a dying 4s iphone battery and needed replacement. Of course the "Genius"'s that decided to replace a double zero phillips with a pentalobe screw figured that there are no hacks for the screw- they assume they can screw us too by overcharching for a simple repair.
Once I received both of the drivers, replacing the battery took all of 5 minutes. Phone is as good as new.
Not a difficult repair, anyone with a simple knowledge of knowing how to turn a screw can do this. Make sure you look at some online tutorials to make sure they can actually do this.