[youtube=http://www.youtube.com/watch?v=W7xuEp8H1n4]
The DSLR Camera Remote app from Oregon-based onOne Software lets you remotely adjust settings (shutter speed, WB, aperture, etc.), view previously taken images and trigger the shutter on your Canon or Nikon DSLR from your iPhone or iPod Touch. If LiveView is one of the features on your DSLR then consider it a feature on your iPhone, too.
The Pro version is a hefty $20 but comes fully featured while the Lite version costs $2 and only fires the shutter. A list of compatible Canon and Nikon DSLRs can be found here.
DSLR Camera Remote Lite [iTunes]
DSLR Camera Remote Pro Edition [iTunes]
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