I recently reviewed Rav Power Luster 3000mAH this is an external battery in the color gold. I was really excited to try this as if I forget to charge my cell phone I can attach it to the bottom of this and it will charge it quick with no problems. This is a slim design and is 4.33 inches tall and 0.9 inches wide it is also a flash light. You can fit this in your purse or in any pocket to carry with you this is very lightweight as well. This is compatible with Apple, Samsung, Motorola, Nokia , Amazon Kindle among a few others visit http://www.ravpower.com/
ravpower3000gold.html to learn more.
My Opinion: I love it and it works well and charges the battery very quickly. I love the size and how lightweight it is and portability. This also works well for charging i pods
Besides what I got they have RavPower Wall Charger, RavPower Dual USB Travel Wall Charger, RAVPower Orbit Qi-Enabled Wireless Charger and so much more.
Disclaimer: I was not compensated for this review this is solely my own opinion which may differ from yours.