You can have all the devices you want but if they run out of power then you have a lot of paperweights. One must-have device when on-the-go is a portable charger and the new Peak 6000 from myCharge is my current choice.
The palm-size Peak 6000 will charge the average smartphone 4 times and also charges iPad and other tablets. It can charge up to three devices at once with its built-in Apple and micro-USB connectors plus a USB port for charging many other devices.
The fold-out wall prong allows the device to recharge and an LED indicator shows the current charge level. According to the manufacturer you can get up to 27 hours more talk time and up to 134 more hours of music using the charger.