Top 15 App Accessories for iPhone and iPad

The Jawbone Up wristband ($100) uses several sensors and a motion-tracking engine to track your sleep, diet, and exercise habits--and then nudge you to do something about them. The iPhone and iPod Touch companion app stores and displays that data. It also helps you monitor your diet by prompting you to photograph your meals and asking how certain foods make you feel.

The Parrot AR.Drone ($300) is a camera-equipped quadricopter that you control with your iPhone, iPad, or Android phone. The drone connects to your device via Wi-Fi. You can pilot it through the free AR.Freeflight app (iOS, Android) or play several dedicated free games.

Developed by former Apple iPod and iPhone hardware development chief Tony Fadell, the Nest touch-controlled thermostat ($250) promises to learn how warm or cold you like your house at different times of the day, and then set those temperatures automatically. The free companion app for iPhones (soon on Android too) allows you to control the Nest remotely, so the house is at the perfect temperature when you come back.

The Griffin Beacon ($70) turns your iPhone or Android phone into an easy-to-use, never-lost remote for your home entertainment center. The Beacon pairs with your phone via Bluetooth and works with the free universal-remote app from Dijit to put you in control of your living-room gadgets.

Dock your iPhone or iPod Touch in the PocketLoops keyboard ($80) to create or remix your own beats and songs. You can choose drum tracks--from House to Rock, Hip Hop to Reggae--to match your tastes, and you can use one of the 13 included synths, from organs to pianos. You can also record yourself with backing instruments, play a melody over the top, and share the resulting tune with your friends.

If your child loves to color and you don’t mind losing your iPad for a while, Crayola ColorStudio HD ($30) could be a perfect gift. This coloring book comes with the iMarker, a digital stylus that looks like a Crayola marker and can double as a crayon, a pen, or a paintbrush. The companion app offers pictures, animations, sound effects, and music, and can differentiate between the stylus and finger taps and swipes.

Smaller and easier to use indoors than the AR.Drone, the Helo TC Helicopter ($50) is controlled by a free iOS app. To steer, you can either use an on-screen joystick or just tilt the iPhone to move forward, backward, and side to side. The Helo TC can land itself automatically. The remote, called Flight Deck, connects to the iOS device’s headphone jack to translate your commands into infrared signals beamed to the chopper.

Strap your iPhone to the AppBlaster plastic gun ($45), and you can shoot virtual enemies in your living room. The free companion shooting game uses the camera on your phone and superimposes aliens floating above your couch, for instance, or in front of the TV. As you aim and fire, small faux fingers on the gun tap buttons on your phone's screen. The three games available so far for the AppBlaster allow you to shoot alien invaders, empty cans, and clay pigeons.

From the makers of AppBlaster, the upcoming AppRacer ($80) is an off-road buggy that you control through a peripheral plugged into your iOS device's headphone jack, plus a control app. You steer the car by tilting your mobile device (the product uses the accelerometer to track your movements).

The Wi-Fi Body Scale ($160) connects to your iPhone or iPad to automatically record your body weight, your lean and fat mass, and your body mass index (BMI). The companion iOS app gives you an overview of your weight over time, so you can easily keep an eye on your fitness. Family members can set up their own profiles with the scale, too.

If you enjoy retro games, check out Atari Arcade Duo Powered ($60), which brings the feel of classic video gaming to your iPad. The joystick and buttons work with the Atari Greatest Hits app, so you can play dozens of games (including multiplayer titles) just as you would on a traditional arcade machine.

The GameChanger ($80) is a combination iPad dock and playing board for several games. To play either The Magic School Bus or Animal Mania, you place the iPad in the middle and spin a virtual wheel on the tablet to determine how far to move. The app tracks each player’s progress, and the board itself comes with two different skins, one for each game.

The Mophie Pulse ($100) turns a fourth-generation iPod Touch into a portable gaming console. With the Pulse, you'll get vibrating feedback from your games, and better sounds via the integrated stereo speakers. The Pulse also includes an extended battery with an LED that indicates how much juice you have left.

Paired with the Garmin Fit iPhone app, the ANT+ fitness accessory ($50) can track your running, walking, and cycling routes and speeds, as well as how many calories you have burned. The little device can also connect to some fitness and gym-workout equipment, such as treadmills, bikes, or rowers that support the ANT+ system to track your exercise routine, heart rate, and caloric burn.

Turn your iPhone into a realistic pinball cabinet with Pinball Magic ($35). It has folding legs for easy transport, and the companion app is free in the App Store. It has an animated backbox with LEDs behind the glass, and it offers a few multiplayer games, too.

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