iWriteWords is a highly-rated app to teach kids to write their letters at first, and then words. There are tons of these types of apps out there, but what makes this one special is the delightful special feedback it gives when you are on track, vs. off.  The sounds build off of the prior one and are so well coordinated with the visual changes that it just makes you smile—and kids love it, while they are secretly learning to write!  I first heard of this app in an article titled “The iPad: a Near-Miracle for My Son with Autism” and have tried quite a few others, but iWriteWords wins.  It even has a “vortex” in a corner of the screen where successfully written letters get sucked into, or can be dragged playfully. ($2.99, iPad or iPhone).
If you do need something easier (less audio/visual feedback when off track), try Letter Learner ($2.99, iPad only). Beautiful chalkboard motif, but does not teach as well.
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Its likely your child will fixate on something and learn everything they can know about it. For my son, it was letter, numbers, and…car logos!  Any car driving by he can tell you what make it is. His favorites are “W” (what he calls BMWs) and “Acura”.  So naturally I looked for any iPad game with car logos and behold, iCar Logo was there. Developed by the same person (Jenny Sun) as US Puzzle Map, this is decidedly less polished but works nonetheless. $1.99.
If car logos are not your child’s thing, there are a number of other matching game apps, including Animals’ Matching HD which makes animal sounds representative of each one tapped on, Find me! which is not tile matching at all but pattern recognition, and Memory4Kidz (for iPhone, Blackberry, and Android).
United States Puzzle Map is great for learning geography and fine motor (dragging and dropping) skills.  It says the name of each state as you pick it up.  Also for iPhone/iPod touch but much nicer on the larger iPad screen. Available for other countries and Europe. The US version taught my son all 50 of the states and where they belong on the map after just a couple days of playing! $2.99 on sale for $1.99.
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Monkey Preschool Lunchbox has beautiful graphics/animations and many mini-games as you progress to pack the lunch (which will never be fully packed!) for the monkey. My son played this for 3hrs straight on a flight. He (3yrs old) instantly figured out all games except for the puzzle piece one. Demonstrated it once, and he never had a problem again. $0.99
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First Words by Learning Touch is a great first game for your child. Drag the letters to their place in the word, and hear the letters. When word is complete the screen animates and sounds like the object. They have a free Sampler version and the expansive First Words Deluxe ($4.99). There are also Spanish, Japanese, and other foreign language editions available. For iPad or iPhone.
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