Can someone tell me about a portable power charger?

[patphil]

3. Just Google "Best portable phone chargers".

There are literally hundreds of these devices out there, at very low prices.
You can get them for your phone, tablet, or even your laptop.
They're great to keep on hand if you have a power failure, or are going camping or hiking.

Mobile hot spots are entirely different, and much more expensive. But then, most new smart phones are able to be used as a hot spot anyhow.