TigerText is an iPhone application which promises to delete text messages from the receiver's phone after a set period. Billed as a tool for adulterers (classy!), the application kinda works, provided you're loose enough with your definition of "text message".

Despite the PR pitches, the application has nothing to do with SMS messages. Instead, TigerText users can send messages to each other using TigerText, and specify a valid period for each message. After this time is up, the message is deleted from the TigerText servers and therefore from both sending and receiving iPhones. You can also choose to have the message vanish as soon as it has been read, in a kind of modern-day Mission Impossible homage.

This is fine for pre-arranged clandestine communications, but has the same problem found with any service like this: the recipient needs to install software. And if they don't have it, they will get a regular SMS prompting them to install it, a very annoying "feature."

If you can get friends to sign up, it is at least a cheap SMS alternative. The app is free, and you get 100 messages when you install it (valid for 15 days). After the trial period you can buy 250 messages for $1.50, or pay $2.50 for unlimited texting. Receiving messages is always free, and the application also works fine on the iPod Touch. Now you just need to make sure you never go home with lipstick on your collar.

TigerText [iTunes. Thanks, Jeff!]