If you have a tablet or smartphone running Android version 4.0, install this official gmail app. This is the default gmail app that comes with ICS and it has some experimental features that one can enable. Do note that the app is very buggy on Honeycomb while it works pretty well on ICS. The experimental features need to be enabled and the two features are:
- Full text search
- Drag and drop contact chip. Using this feature you can drag contact names between To/CC/BCC fields.
So, go ahead and install the apk from link mentioned above and enjoy this new app. And btw, it's official gmail app that we are talking about.