Most portable batteries have enough capacity to charge a smartphone once, maybe twice. What if you need something that can fully top up a smartphone several times over? We're partnering with Dodocool to give away 15 of the company's 20,100mAh batteries, plus we have a 39% off coupon if you want to buy one.
This contest is now over.
The final results are listed below. If you've won, you will be contacted in the near future. Congratulations!