There are some nice aspects to the phone aps though. Not sure how the Garmin works, but when I finish my ride using cyclemeter it sends a link to my email, and all my data is there to view by clicking the link.

IMHO cyclecomputers are more "solid"...they just work.....so I would probably never rely on an Iphone as my ONLY device, but I have it with me anyway and running cyclemeter with the screen off really does not use much power, I did a 4 hour ride and it used something like 10% of the battery ??

Bill