Looks like you clicked on the "I'm mobile" link from Yahoo! Messenger.
What does "I'm mobile" mean?
When a friend's status says "I'm mobile," they are using a mobile version of Yahoo! Messenger and can send, receive, and reply to instant messages from their phone.
Get Messenger for mobile
Enter your mobile number.
Yahoo! will not use this number for marketing unless you've given us permission elsewhere. This number will only be used to send you an SMS text message explaining how to access Yahoo! on your mobile device. Operator charges may apply.
Or type this URL into your phone's browser:
Want Yahoo! Messenger for your phone?
Stay connected with your IM friends from your phone—it's easy to send and receive Yahoo! Messenger instant messages when you're mobile. Learn more.
Yahoo! Messenger for BlackBerry®
Get Yahoo! Messenger designed just for your BlackBerry—it's one of the best mobile Messenger experiences available.Get it here.
Yahoo! Messenger for iPhone
There's a new, enhanced iPhone version of Yahoo! Messenger available now, at the App Store in iTunes®.
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