Groupon offers the Mota 2,400mAh Battery Case for Apple iPhone 5/5S in Green or Pink for $34.99 with free shipping. That's tied with our mention from two weeks ago as the lowest total price we've seen for this battery case. (It's a current low by $4.) This low-profile case features a built-in 2,400mAh battery, which is purported to nearly double the life of the phone. Deal ends August 29.