As one of its daily deals, Best Buy offers the LifeCHARGE Battery Case for Apple iPhone 5 / 5S in Black, model no. ONT-PWR-35171, for $32.99 with free shipping. That's the lowest total price we could find by $47, although we saw it for $8 less in December. It allows for up to eight hours of additional talk time on 3G networks and a built-in 2300mAh lithium-polymer battery. Deal ends today