I have a Galaxy Nexus. I bought this assuming it would charge my phone faster than a 0.5A computer USB port. This charger ONLY fast charges Apple products. When connected to an Android phone it will charge at USB data connection speeds (0.5A) and not speeds comparable to the stock wall charger achieves (1.0A).
PROS: It does work as it intends to work.
CONS: On Android devices, this charges at 0.5A (slow charging). This is misleading as it advertises 2.1A.
There are 2 charging standards for micro-USB devices to charge above the standard 0.5A USB power draw. If you were to plug in a device that draws over 0.5A into a computer with no safeties involved, it could be damaging to the computer.
Apple uses proprietary circuitry in iPad chargers that looks for certain signals to allow the device to draw more than the standard output. Every other company (Android and Windows Phone) uses a simple short across the two data contacts in the USB connector that tells the device that it's plugged into a power port, not a computer, and the device then knows that it can draw more than 0.5A. When I plug my non-apple phone into this charger, it thinks it's plugged into a computer and only charges at USB rates.
I've done my own fix on a few other chargers by simply soldering across the connectors inside the charger, but I can't figure out how to get these chargers open without damaging them. I guess I'm not sure if that's a plus for build quality, or a minus for repairability. Either way, I'm disappointed with this product.
PROS: 2.1 A for proper devices Inexpensive
CONS: Does not charge android devices at 2.1A! Large size
I bought a couple of these to charge my android smart phones. Unfortunately they don't have the data+ and data- pins shorted so my phones only draw power from them at 500ma (USB charging speed). It would have been nice to have this pointed out in the description or knowledge base before ordering. I believe I can get a USB cable with those pins shorted but now I will have to carry both a charging cable and a data cable with me.
CONS: Does not have the data pins shorted for android devices.
This device should be labelled an Apple charger instead of a USB charger, as it lacks the proper signalling on the data pins for USB devices to charge faster than from a computer port. Also, the noise it makes when idling or charging is quite annoying - basically defeats the point of having an extra charger to leave plugged in in a handy spot.
To salvage my purchase without the hassle of the return process, I opened this thing up (also not easy), made the proper connection between the data pins, and slathered the primary inductor in CA glue. Unless you're either willing to do this, or are looking to power Apple devices somewhere noisy like a dance club or factory floor, it's probably better to steer clear.
PROS: Produces 5 volts.
CONS: Doesn't conform to USB charging spec. Makes constant annoying noise.
I usually wait about a month to use purchased products before writing a review. In this case, I've waited about a year. Reason being, I was really worried about the reports of failure. In my case I can happily report that my 10273 is still alive and kicking. I have it at work and it is used every day, so I have definitely put miles on it. To get a true 2.1 amp charger for this price is ridiculous, I plan to order a batch of these for all the managers here. Anyway, in my case, this charger is top notch (actually charges my Ipad4 faster than the Apple supplied one) and a great bargain.
PS For all those that say you were tricked and thought there a cable was included, hopefully it's a lesson to actually READ the item description. You will fare much better that way, I promise.
PROS: Amazing bargain for a true 2.1amp charger.
CONS: If you can find a fault with true 2.1amp charger for this price, you may never be pleased
The first one I received did not work on my Nexus 7, and I thought it was a dud Monoprice sent me another new one right away. The second one was exactly the same as the first one, which made me to do some research. Apparently, apple devices and most of the none-apple devices accept different "high amps" chargers: apple devices requires there is a resistor between the USB's D+ and D- pin, while the others normally requires a short circuit between these two pins.
Apparently, this charger goes with apple way. And, if you want to use it on none-apple device, you need to buy a "charge-only" usb cable which shorts the D+ and D- inside the cable. Considering these kind of "charge-only" cable sales around $7 at Amazon (could not find it at Monoprice), I would probably go with a dual-port (one for apple, one for the rest) charger from Amazon.
PROS: The customer service at mono price is awesome. They sent me a replacement within 24 hours.
CONS: Out of box, this charger can ONLY work with Apple devices. Using the standard USB cable, it does not work with my Nexus 7 or old black berry cell phone. You need the so-called "charge only" usb cable in order to make it work with these none-apple device.