Everybody knows that leaving appliances on but now that many cell phones have switched to USB charging, it's easy to just leave your phone plugged into the computer and leave the computer on. While Apple provides a USB wall charger, it's pretty small and easy to lose. It's also easier to leave it connected to the computer you sync with. Furthermore, the wall charger often isn't compatible with the most protective cases. This makes using it annoying.
Energizer has developed an inductive charging technology which they call Qi. This technology uses a series of antennas and circuitry to send power across short distances without wires. It's a bit odd to think of, but it works.
Only two devices are currently supported by the Qi, and they both normally can charge via USB. These devices are the iPhone 4/3GS/3G and the Blackberry Curve 8900. Both devices require a slight modification to work: The iPhones require a case that covers the dock connector and the Blackberry requires a replacement battery cover. Unfortunately, I only have an iPhone 3GS and could not test the charging capability of the other phones.
The charging pad supports two devices at once, so if you and your signifcant other both have a supported device, you can use just one wall power outlet. There is also a USB charging port on the back of the pad for charging other devices such as a third iPhone or a Kindle.
The neat thing is that the Qi really does work. It's neat to see your phone simply be laid on the pad and watch it fill with power. It doesn't work all that well, though. I'm not sure if this issue is only with the iPhone 3GS, but I tested two with the Qi and they both had the same issue. When fully charged, the Qi cycles into a no-charge mode. This turns the charging off saving electricity. When the iPhone drops enough in charge, it turns it back on, causing the phone to vibrate as if it were plugged back in. According to the Energizer I communicated with, it may be because too many programs were open on my phone at a time causing too high of a power drain. I don't think so. I only have a few programs enabled with Push, ones that I would imagine most phones have too: Mail, Facebook, Fring, Google Voice, and eBay.
This problem is especially annoying while sleeping. I kept the Qi in my bedroom and after every 10-15 minutes I would hear my phone vibrate around on the pad. Eventually, I couldn't take it anymore and went back to my wasteful ways of using my computer to charge.
If Energizer can work out this issue, the Qi would be almost perfect. The iPhone Case is awesome. It's a little bit bulky but it's also very sturdy and feels strong enough to handle a decent impact. I would replace my current iPhone protection with it permanently if it didn't wake me up. I also liked its extra USB port. The only other issue I had with it was that the AC adapter cable came out easily. Very easily. It's stubby and small so there isn't much friction to keep it held in. A small jostle and it's out, you wake up and your phone isn't charged.
The charging problems may not be evident in the iPhone 4 or Blackberry curve, but I suggest you figure that out before purchasing it. It's a problem that's annoying enough to make you return it if you use it in your bedroom. The added convenience of not having to plug anything in isn't outweighed by the loss of sleep you might get. Oh, and I forgot to mention, you need to buy the iPhone Case and the Blackberry battery cover separately.