Manufacturer's product page
Output: 2 * USB: 5V / 2.1A DC: 9V / 12V 2A
Input: 9 - 15V / 1A
Weight: 9.9 oz
Size: 4.9 * 2.9 * 0.9 inch
I picked up an Astro3 battery back in December, and am glad that I did.
The concept is pretty damn simple: the Astro3 is a standalone battery pack that can charge your various electronic devices when you're away from a dedicated power source. Anker makes them in other sizes, but I chose this model because it has a capacity of 10000mAh.
For those unfamiliar with the unit of measurement, it means milliampere-hour: a battery pack with a capacity of 10000mAh should provide a 1A current (1000mA = 1A) for the duration of 10 hours. If you look at the battery in your phone, camera, or other handheld device, it should also have a mAh capacity listed. My Galaxy Nexus, for example, has a factory battery capacity of 1850mAh. So putting it into perspective, the Astro3 has about 5.4 times the energy capacity of my phone.
The Astro3 has two USB ports and one DC output port (the latter of which can be switched between 9v and 12v output). The unit features an "on" button, an input port for charging, and 4 LED lights that indicate remaining charge.
In the package you'll find a bunch of cell phone specific adapters, laptop adapters, and cords to go with them. If your phone was made within the last decade, however, it most likely plugs into one of the aforementioned USB ports. If you fall in that camp (as I do), you won't need ANY of the adapters included.
Astro3 with included adapters
Usage is almost as simple as you would assume. To charge the Astro3, plug it into the wall. To use the Astro3 to charge other devices, plug those devices into the Astro3, and then press the power button. It's this last step that is very easy to forget. And believe me, it's frustrating as hell to plug your phone into it, come back 20 minutes later, and realize that your phone hasn't been charging because you forgot to turn on the Astro3.
It's not as if the device tricks you in any way: whenever it is charging your device, it will have illuminated circles to indicate how much capacity it has left. But making sure that my charging source is "on" is just not something I'm used to.
(Note: there is no "off" button. It turns itself off as soon as you unplug your devices from it)
Astro3 charging my Galaxy Nexus and Hero3
simultaneously, with the DC output cord unused.
Note the two illuminated circles, indicating the
Astro3 has approximately half of its charge remaining.
But assuming you actually remember to turn on the Astro3, it's great. I'm able to get 5 full charges on my phone, which is about 93% of the advertised capacity. Between power loss during transfer and embedded safety features (which can limit how deeply a battery is discharged), I consider this to be great performance.
With its solid performance, I find the Astro3 to be a critical travel tool. It's great to spend a long flight playing games and watching movies without any fear that my phone will be low when I reach my destination. After all, I need it for GPS navigation whenever I go to a new city.
Another aspect of the Astro3 I find convenient is the fact that I can have a consolidated charging station. I don't know if it's just my crappy luck, but it seems like most hotels I stay in either lack a decent number of outlets, or have them located in inconvenient places. The Astro3 can be charged while it is charging other devices, so if you only have access to one outlet, you can still charge multiple devices. Plug them all in to one outlet, hit the pillow for the night, and you'll wake up with everything fully charged.
Astro3 charging off of wall power while
simultaneously charging the attached
Galaxy Nexus and Hero3
Take note that the two USB ports are slightly different and may charge different devices at different rates. Some devices, such as my phone, try to detect whether they are plugged into a computer USB port or a powered USB port. Depending on what my phone determines to be the case, it will draw current at a slower or faster rate (there are workarounds for hacker types, but that's another conversation for another time).
It is my unconfirmed suspicion that one of the USB ports has the data pins shorted, while the other does not. If you pick up an Astro3 I would suggest you test two things:
- Will your devices charge on both USB ports?
- Does any given device seem to charger faster on one port than the other?
Theoretically the Astro3 can even charge your laptop, though none of the included adapters fit my Toshiba. I don't really care, however, as it's not something I would ever do. If I'm using my laptop, I'm near wall power. If I'm not near wall power, I'm using my Galaxy Nexus phone or my Nexus 7 tablet.
Besides the need to turn on the Astro3 (which I only consider to me a minor nuisance), the only possible complaint I have is the weight (almost 10oz), but I knew what I was getting myself into when I chose the 10000mAh size. As you can see on the previously linked manufacturer's page, they make an entire line of Astro products, with the Astro3 being the largest. At the opposite end of the spectrum is the Astro Mini, with 2600mAh at 2.7 ounces (assuming a similar efficiency as its larger brother, I figure this one would give me about 130% charge on my phone)
I would recommend a new Astro product to anyone who travels with electronics... which really means anyone who travels. I purchased mine on Amazon, where I see you can also get used versions of the Astro3. Just my personal stance, but I would recommend against purchasing a used one. The life of any battery will be greatly affected by how that battery is treated, and without personally knowing the seller, I wouldn't take a gamble on a used one.