If you need as much juice as you can get while on the go, then this 10,000mAh portable charger should fit the bill perfectly. This massive battery pack features dual USB ports (one 2A, one 1A) so you can charge two devices at one time, enough juice to charge most smartphone at least four times, and compatibility for "tablet PCs."
While it's going for $90 on Amazon right now, you can score one for $50 from Daily Steals for today only. That's a pretty good deal, especially for a portable charger packing that much on-the-go power. Hit the link below to buy.