Thank you for that excellent question
The Niper has a powerful Battery – Lithium Ion polymer – 3.7v , 420 mAh.
Depending on the kind of battery you have in your phone (1800 mAh or 2000 mAh.), the Niper can give you about 20% - 30% from 0% battery. The Niper Charges a cell phone at 500 mAh current.
I don’t know all the details regarding NiftyX's, and I don’t like to talk about other projects. But I can tell you that the Niper is a small power bank, AND its can transfer power from one phone to another. It acts like a bridge between 2 phones, which practically means that you will never be left without power. You can contact the Niper nearest to you and recharge - or they can contact you for a power boost. Show me another product that has those two great features together!