Google released a new Gmail Labs feature that show you a "robot icon" next to people who’re currently using Android 
phones in Gmail chat mode. In the pic, Shirley is online with Android, Nicolle R. is using regular Gmail chat, and Chris I. is currently away but also on Android. Slatka is not an angry robot — she's online with Android but currently busy. These icons help you decide whether to tailor your conversation to type of device that your chat buddy is using. For example, when you know the guy on other end is using his Android phone, you may decide to send shorter, more concise chat messages. When your chat buddies log into Gmail, their presence icons will revert to the traditional red, green, and orange status bubbles. In addition, if your chat buddy happens to be logged into both Gmail and Android chat then the traditional Gmail status icons will be shown.
Posted on Nov 18, 2009, 3:45 pm, UTC
Wao this is the great feature, From last few months that robot sign was a mystery for me :)Google slowly but gradually penetrate Android OS in mobile market now lots of good apps like Truphone, Vopium, fring has their apps for android phones.