There is a problem with the iPhone on entering a "period" at the end of a sentence. Evidently the period isn't included with the rest of the alphabet, so entering a period and moving on with another sentence is an aggravating process. Well David Chartier from TUAW thinks he has an easy solution:
simply press that ".123" key normally, type your period and then hit the space bar - the iPhone realizes you've just ended a sentence and are beginning another, so it automatically switches back to the alphabetical layout.
[Update: It appears my trick works with any character on the punctuation/number keyboard layout: press the .123 button, hit a number or punctuation character, then press the space bar to switch the layout back to alphabetical. For some characters that typically have a letter after them, such as an apostrophe, the keyboard seems to switch itself back automatically without any interaction on the user's part; not even a space bar.]
Now I have a tip on using the period when using your Windows Mobile Device. I have verified it on the Palm 700W, Palm 750, KJAM, JasJar, Cingular 8525 and my NEW Blackjack ... JUST PRESS THE PERIOD KEY.
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