I was excited to find this app after switching from Windows to Mac. However, while I was trying to update my GPS Device with this app I got an error (sorry, cant remember the exact wording of it). It said to re-try, so I did, and it couldnt find my device. I couldnt even power up my eTrex Venture HC, which was working just fine just moments before. The screen on the GPS would flash once when I tried to power it up, but then - nothing. I contacted Garmin by email and they gave me instructions on how to reset it, they called it a Boot-Block function: Press and hold up on the THUMB STICK, Press and hold POWER for 5 seconds, release, and continue holding up on the THUMB STICK. This did nothing. They then said I would have to send it in for repair and it would cost $79 because I am past the 1 year warranty period. Kind of pathetic to pay half of what its worth for repairs. And very pathetic that their software killed their device and they wont stand behind it. Beware when using this app!