One of the cooler gadgets for iOS users to show up at this year's CES was the hipKey. The little keychain-sized dongle can attach to nearly any item, helping you figure out where you lost those car keys for the hundredth time, or even keep track of the kids. Today, the device has appeared on the Apple Online Store for immediate purchase.

"The hipKey is a high tech way of keeping track of your valuables," reads the description on Apple's Online Store. "Simply attach the device to the item of your choice and you’re ready to go. Made of a sculptured one-piece anodized aluminum ring surrounded by high-quality plastic parts, its sleek oval form fits perfectly in your palm or pocket. You can even attach it to your keys."

The hipKey kind of resembles a little Apple logo--or maybe a really hungry Pac-Man. But more important than its light weight or small size, the hipKey pairs with your iOS device via Bluetooth 4.0 to act as a proximity sensor. 

Four modes are available, including an alarm mode to notify you if your iOS device gets too far away. A handy function in case you, say, leave an incredibly valuable and secret iPhone prototype in a bar. Child mode essentially works the same way, letting you know if a kid wanders off. Motion mode notifies you if the item the hipKey is attached to is moved--keep it in your coat pocket to thwart would-be thieves, for example. Find Me mode will lead you back to a set of keys (or anything else).

Battery life on hipKey sounds pretty decent, with a single charge lasting two to four weeks. The hipKey recently sold out on the UK store, but as of this writing, the device is in-stock on both Apple Online Stores. The associated app is free on the App Store, but purchasing the hipKey itself will set you back $89.95.

Expensive? A little bit. But stick a hipKey on the last beer in the fridge, and your roommate will think twice. Money well spent.

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