Bests & Worsts Reviews from Amazon

***I received an updated version of this item from RAVpower for free recently. It is now rated at 3000mAh and I definitely feel that the new one holds more charge. It also recharges much faster and the flashlight is brighter. The only change I didn't like was the button for the flashlight. It's not a simple on/off anymore. Each button press now goes from solid bright, solid light, and then strobe. It could take up to three button presses for the flashlight to actually turn off. Overall, this is a solid improvement. Price also didn't go up. 5 stars***** I just tried a test run and it performed ok. I used it to charge an LG Nexus 4 which has a 2100 mAh battery inside. The phone was mostly in sleep/idle when being charged. The following is not in any way a professional or scientific test, but it will give you a general idea of the charger's performance. For the first run, this unit charged the phone up +68% in 3 hours which is equivalent to around 1430 mAh (23% charge per hour). Given that the RAVPower charger is rated at 2600 mAh, the test resulted in a 55% charging efficiency. The flashlight function is not very bright. It's comparable to one of those tiny button keychain LEDs. It may come in handy when you don't have any other light source. The LED flash on my phone is at least 5x brighter with a wider pattern. I purchased this on sale and I don't regret it. I'll be happy if it can charge my phone from near dead to 3/4 full battery. The unit itself is very pocketable and it comes with a handy, short micro usb cable for charging. *New batteries need a certain number of recharges to get optimal performance and I will update the review with more tests. I'm sure it will perform a little better upon further review. The actual battery inside this unit is supposedly a Samsung 18650 2600 mAh battery, this battery type is commonly used in LED flashlights and eCigs. Updates: Test 1: I used my own 3rd party micro usb cable. Phone charged : +68% (approx. 1430 mAh) in 3 hours Charge Rate: +23% per hour Charging Efficiency: 55% Test 2: I used the short cable provided in the packaging instead of my own micro USB cable. Better results. Phone charged : +76% (approx. 1600 mAh) in 1.87 hours Charge Rate: +41% per hour Charging Efficiency: 61.4% Comment: The new results (faster charge & better efficiency) changes my review from 3 stars to 4 stars. I recommend using the included cable. Test 3: Phone charged +70% (approx 1470 mAh) in 1.75 hours Charge Rate: +40% per hour Charging Efficiency: 56.5% Test 4: Phone charged +67% (approx 1407 mAh) in 1.62 hours Charge Rate: +41.4% per hour Charging Efficiency: 54.1%