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Question: If my i pad is completely dead can I run plug my device directly into external battery to operate for many more hours or must  I charge first.
Document: At first i though it was an impulse buy. Days later i realized it was the best thing i purchased on amazon. Your guaranteed to never run out of battery on your cell. I take it with me camping or when out at the beach. I have charged my iPhone 10 times with no need to recharge it. Even in the car, i prefer to use the external battery rather then the usb port to charge my phone since its a lot faster.
Works great, can run my iPhone 5 with screen constantly on and GPS enabled all day and the battery only goes down less than 25%. I use it on my bike for tracking my route. One quirk which I'm not sure is due to the battery or the iPhone. To get the phone to recognize the battery in charge mode the phone needs to be plugged into the lightning connector end of the cable first then plug the USB connector end into the Battery.
The blue LEDs on the front will light up and blink as it's charging. When it's full you'll see all four LEDs lit solid. I don't know how long it takes to charge from completely empty because mine came 3/4s charged and I have yet to run it down. From 3/4ths down it took around two hours hooked to a 2.1A charger, so probably 8 hours from empty.The switch on the left side of the unit turns on the meter with one press.
This product only worked the first time I charged it and then has never charged to its full capacity again. I leave it plugged in for 24 hours and it only reaches the second bar of being charged. From there it will only charge my phone fully 2-3 times before being dead. I wouldn't recommend this product to anyone. It's a waste of money.
Although I haven't tried it.6) When traveling on the airplane or van, I left the device in my backpack and simply brought out the end of the wire for charging my phone, so it was always charged. With the two ports, I was able to charge both my phone and my friend's phone at the same time. The device &#34;begins&#34; trying to charge your phone, or whatever you plug in, when you plug the wire into the external battery.
At first, it was great! It didn't charge my device as many times as it should have (1700 mAh battery, should have been charged about 12 to 13 times) but I was able to get a nice 6 or 7 charges, so I wasn't too mad.One day, the cord that came with this device broke (or so I assume) and I tried to use a different USB cord, but the charging was very slow.
I used this device, EC TECHNOLOGY 22400mAh Portable Ultra-high Density External Battery, on international travel. It was great. A couple of things to note:0) Charging your phone or whatever takes the same amount of time as it takes if you were to plug your phone in the wall. So it works the same as other charging methods for your phone.1) It takes quite a bit of time to recharge this external battery device.
so be warned, this thing is big. it probably wont fit into a tiny purse but its definitely worth the weight if you never EVER want to run out of power on your device. the 2A port allows you to charge as if you were plugged into a wall outlet with a tablet's adapter. i havent even used the 1A port since i only ever need to charge one device at a time. i estimate about 10 recharges to my nexus5 before i need to plug this thing in for a charge.
This battery sucks. I got it and tried to use it after properly charging it. it charged my phone completely on the first time but after that it wouldn't charge anything else now I'm stuck with this POS.
Plug it into my S3 phone that is at 88% charge.Must press the side button on battery to get it to start charging. Then is stops charging after about 3 minutesReturning it for another brand
Answer: It will charge it while the tablet is in use.  If the tablet has no battery life it may need to charge for a few minutes before it will power on