reMail for Gmail is a utility app that lets you download all the email from any gmail account and search the full text in those emails. The app also allows you to reply, forward, delete individual mails.
The good part of the App is that you can either chose to download all mails or any particular labels (labels is a similar to folders feature in Gmail). The app is smooth and feels much lighter than the default mail app on the iPhone or iPod touch. The utility value of this app is pretty less as the default mail app would let you search all emails on the server if you are connected via wifi or gprs. So as a free app that it is currently being on sale, its good. Else I would think before spending $1.99.
The app doesn’t consume too much memory on your iPhone and the app developers estimate that 100000 emails will consume only 500mb space in your inbox. And that is because it doesn’t display any graphics, only plain text.
[one little issue i faced when reMail was downloading emails form the server is that my default email app was not sending emails. Not sure if it a conflict, but just something that occurred] – Ok false alarm, was an issue with my jailbroken iPhone 2G.