This classic beautiful power bank is inexpensive although it works great and compact

Great power bank

One thing to remember is power banks/portable chargers, depending on their quality, will take a bit longer to charge than your actual device; but when fully charged, this one offers a charge time for your phone, tablet or other USB devices that far supercedes one full charge on your phone.

This is Great and beautiful portable power bank

This is a good and 5-star power bank