The
Google Mobile App available from the App Store for Apple
iPhones would have to be one of my favourite apps. Basically
it allows you to search Google via a locally installed application
on your iphone, without having to first start up Safari, and
subsequently waiting for the results to download in HTML format
(which adds unnecessary overhead).
Of course those of you with a 3G iPhone may not be too fussed
about that extra overhead, but I'm still using a 2G iPhone, and
internet browsing over GPRS is pretty damn slow, so any way of
getting to what I want quicker is a good thing in my eyes.
I just read a great little tip today about the Google Search
App... if you type in a site name (eg: apple.com), and then hold
your finger on the search result for www.apple.com, you'll see the site
url appear in the search bar at the top in blue... now any terms
you add after that will do a site search of the url in the blue
search bar. Yet another shortcut to finding exactly what you
want, when you know where it is.

Thanks to
LifeHacker - one of my favourite sites on the net - for this
hot tip (and the image).