Thinking before buying can be the right thing to do many times. If you purchase anything without any idea so, it may not be of much use.
So, here we have a large variety of mobile power banks but it is the responsibility of the customer that what model he needs.
There can be many diciding factors like the mAh capacity, weight, number of USB outputs and other.
This sense 4 plus power has digital screen by which one can have an idea that how much the power-bank is charged.
Moreover, it has dual ports and hence one can put two devices on charge.