Google has announced that it will quit supporting the Gmail app for Blackberry smartphones, come November 22nd. While users who already have the application installed shall continue to be able to use it, but there shall not be any more updates for the same and the download link shall also be removed.
Google has been working hard to improve the Gmail mobile website, especially after almost all mobile phones started supporting HTML 5, including the Blackberry browser. Of course, more of than not a Blackberry user shall have his Gmail account configured with BIS, a lot of people actually found the Gmail app useful when they had to view emails whose sizes were more than a Blackberry’s stipulated size limit of 3MB.
There's always the native BlackBerry email app too, of course, but it doesn't provide full access to Gmail-specific features like starring, archiving, multiple labels, and most of all full account search — though RIM's Enhanced Gmail Plug-In for its native email client does support those features.
Of course, the Gmail app for Android is the most advanced and user friendly than all those for the other platforms. And it is no secret that Google would like you to rather be on an Android phone, than any other platform.