The U.S. General Services Administration launched a mobile app listing hotel, meal and incidental per diem rates for cities in the continental U.S. Taking into consideration how new the app is, there appear to be a few kinks left to work out, but otherwise, it is great platform for quick access to spending limits.
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GSA launched the app for Blackberry on July 18 and iPhone on July 20, allowing travelers to search for government per diem rates by city, state or ZIP code. For Alaska, Hawaii and the U.S. territories, only Department of Defense locations are listed.
The only glitch I found within the iPhone app was during the search process, where the "Go" button requires several "touches," if you will, before results populate. It seems as though at least one other person is experiencing a similar problem. According to the lone reviewer on iTunes, "Not very useful if you have to know which country a military installation is in. Also, a noticeable lag when pressing the Go button."