Sparrow for iPhone: Download all mails

I use Sparrow for iPhone with Gmail.

Sometimes it confuses me because the unread count for some of my labels doesn't match with the one shown in the Google Mail app (it's lower, presumably because Sparrow doesn't download all mails).

The thing is, that I know the expected unread counts of most labels, and if they differ from the official app, I can't quickly see whether there is something new in or not.

I think for this to work correctly, Sparrow would have to download all mails, or update the unread mail counts from the server instead of the mails it already has on the device.

Is that possible?

Sparrow computes the number of unread emails based on the downloaded emails in the specific folder. That would be possible to show the number of emails based on the server but some servers shows the wrong information, some servers requires to consume lots of bandwidth to get that information.