Everyone is carrying a smart phone & facing battery drainage problem as well, they want to decrease it “how we can reduce the battery drain out problem”, the answer of this question is “Powerbank” which are easy to carry & portable as well. You can easily charge anytime your smart phones, tablets, i-phones without chargers. The capacity of powerbank depending upon the usage of the Mobile & Tablets. Suppose your phone battery is 3000 MAH then either you can purchase 10400 MAH Power bank or 20800 MAH Powerbank which would charge your phone 3 to 6 times. So check your need and buy power bank online.