For me, the best free iPhone app in the Apple App Store would have to be the Dragon Dictation iPhone app. The Dragon Dictation iPhone app allows you to speak in to your iPhone and have your speech converted to text. Your text can then be sent as a text message, E-mail, or pasted in to another iPhone application using the clipboard. Pros:

• Converts your speech to text very accurately
• Offers suggestions for text that wasn't converted from speech to text properly
• Saves you a lot of time

Cons:

• There is a 30 second time limit for dictation, but you can keep adding more text after every 30 seconds
• Requires you to have an Internet connection
• Doesn't work well in noisy environments

I've been using the Dragon Dictation iPhone app for about a week now and have found it really helpful. I still type with my keyboard sometimes but whenever I  need to type an e-mail using this app saves me a lot of time. It really surprised me how accurate this iPhone app was. Check it out by clicking the download link below! Let us know how it works for you.