The iPhone from Apple Inc. has changed the way people use mobile phones. It is a complete internet enabled multimedia phone. It's only been almost four years when Apple introduced this device in the market but there are already thousands of applications created for iPhone.

If you have kids, I'm sure that there are times when you wish there is something you can give your kids to keep them from running around too much, or keep them busy while waiting in line at the grocery or at the doctor's clinic. Well the following iPhone apps will surely keep them busy and smart too! Not to mention these apps are free to download.

1. Scribble (ages 4 and up) - Scribble turns your iPhone or iPod Touch into a sketch pad with tons of colors, pen size, and photo options to choose from. Kids love to sketch and this application is what you need. And after you have filled the whole screen with scribbles, just shake the iPhone to erase and start a clean screen… how cool is that?

2. Freshwater Aquarium (all ages) - this iPhone app is not only fun for kids but for grown ups as well. You can choose to manage three tanks that you can fill with several species of fishes. You can feed them to make them grow, play games with them, sell or breed them. You can basically do lots of things. All fish graphics are realistic artwork.

3. Kids Bingo (ages 6 and up) - this game is educational. It helps the kids learn number words and have fun at the same time.

4. Peanut Butter Jelly Time! (all ages)- who does not know this dancing banana which spread like a virus on the internet with a very catchy song. Now you can get amused by PBJ right on your iPhone. Kids will surely love this.

5. Checkers! (ages 4 and up) - this cool game is played on a traditional 2D board and comes with several options. You can play with iPhone or play with a friend in a two player mode using one iPhone.

6. Wooo! Button (all ages) - although this application does one and only one thing... yeah, you guessed it right! It WOOO! every time you push the button. You would think it's boring but actually it's not. Your kids won't stop pushing the button over and over again.

7. Penguin Whacker (ages 4 and up) - you have three time settings to whack as many penguins as you can. The penguins are cute and screech as you whack them. This is so much fun not only for kids.

8. Airport Mania: First Flight (ages 6 and up) - there are different levels that challenges your skills. You can also customize your own airports. Kids will surely enjoy playing this game.

9. Tic-Tac-Toe (ages 4 and up) - this is another traditional game in 2D which has the option for two player mode.

10. iSign Alphabet (ages 4 and up) - iSign Alphabet is another educational iPhone apps that helps kids to learn the entire American sign language.

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