Brando offers this AC to 5-USB Power Adaptor that offers you USB ports even when there is no latpop or desktop computers. The adaptor can charge up to five devices at the same time. It has four female ports and a male port.
The AC to 5-USB Power Adapter includes overload protection, overheat protection as well as short circuit protection. It accepts AC 100-240V input and delivers DC 5.4V, 3.0A output. The adapter is priced at $22.