Smartphones and Tablets today now serve as a mini laptop. Due to their portability and capacity to do most things a laptop can do, today's generation prefer to own a tablet to laptop. Most laptop companies now have their own brand of tablets and smartphones due to the revolution of Android OS which makes smartphones and tablets affordable for everyone.
Choosing the best power bank

Without energy to power on these devices, they are just useless and due to continue increase in their usage, they consumes a lot of energy which makes their battery get drained off in less time. Imagine you are a type that travels a lot or lives where you have just 12 hours of light in three-four days, how will you cope in such situation after your device went off due to empty battery? this is how the idea of power bank came up.
Today, just like smartphones and tablets, there are lots of power bank in market which brought up the question " How Can I Choose The Best Power Bank For My Device".

What Is Power Bank: It is simply a portable charger for electronic devices like smartphones and tablets. This gadget is highly recommended if you are always away from power outlet ( Traveling) or a victim of non-constant power supply.

CHOOSING THE BEST POWER BANK

When buying a power bank, these are the three things you should note.
CAPACITY

BATTERY SIZE:
The capacity of a power bank is measured in mAh ( milli Ampere hour). It is essential to purchase a power bank with a capacity larger than that of your device because there will be loss of energy during transfer. Therefore do not expect to get a single full charge from a power bank whose capacity is the same as your smart phone ( Assuming your device has its battery rating as 1500 mAh, a power bank of 2000 mAh will give you a single full charge). Although there are power banks that can give you three to four full charge, but it will be expensive and bigger.
OUTPUT VOLTAGE AND CURRENT:
When purchasing a power bank, its output voltage and output current must be higher than that of the device you are purchasing it for. You can easily find the output voltage and current of your device on its follow-come USB adapter.

BUILT-IN USB
It is recommended to purchase/buy a power bank with a built-in USB charging cable. Old power banks lack this capability which requires you to have a separate cable with you in case you need to charge your device. In addition to this point, it is advisable to purchase a power bank that is armed with a set of charging cables or connector adapters for different smartphones or tablets.
QUALITY
It is advisable to go for a power bank that host features like short circuit and over-charging protection.

Read more: http://www.rasaqtech.com/2014/11/tips-for-choosing-best-power-bank-for.html#ixzz3JkXl0Ooi