What's wrong with the Gmail iPhone-optimized web interface?
Again, I have to admit that the web-based Gmail experience on the iPhone is by far and away the best web-based mail client experience I've ever used. So what's wrong with it? Primarily, it's too slow, and it doesn't take advantage of some of the features that native apps have available to them, such as swiping gestures to delete messages, and caching messages for speedy access. The Blackberry I had before I got my iPhone had a native Gmail app available for it, and it was remarkably faster to use than the web-based interface is on the iPhone, while retaining Gmail's thread-grouping functionality.
So now what?
Currently I use both clients, depending on what I need to do. Using IMAP to connect to my Gmail account from Mail allows me to switch interchangeably between either client instantly, which is a nice compromise, but sadly leaves me underwhelmed either way.
So what's more likely, improvements to Mail or a native Gmail client? At this point in time major changes to Mail seem unlikely. Until now it has appeared that a native Gmail client for the iPhone was unlikely, due to the terms and conditions of writing iPhone software for the App Store. Apple has a policy of not allowing software that provides similar functionality to built-in Apple software, making for a complete dearth of fully functional alternative email clients on the iPhone. One bit of hopeful news is that mail clients are finally starting to show up in the App Store, though so far nothing has been released that can rival the functionality of the iPhone's built-in Mail application.
Another interesting factor is that Google may not be all that motivated to create a fully functional native Gmail client for the iPhone when its Android mobile phone operating system is built around a reportedly fantastic native Gmail client. Instead of apparently inhibiting the development of alternative email clients, Apple should be encouraging it, and in particular encouraging Google to provide a Gmail client.
As much as it pains me to say it, given how much of my time on my iPhone is spent in email, I will have to seriously watch the evolution of Android and make a difficult decision when it comes time to replace my iPhone 3G, if there is still no native Gmail client available when the time comes.
TUAW commenter snave points us to a video of Vic Gundotra at Mobile World Congress '09 demonstrating the offline caching features of the HTML5 spec using an unreleased version of the Gmail web app on both the iPhone and HTC Magic, which is pretty much exactly what I'm asking for here. If this post touched a nerve for you, the video below should get your motor running.