Mt Whitney Zone Forums General Discussion Mount Whitney Hike: Spot or Satellite Phone

Either of those will work on the Whitney trail. Spot is much cheaper and can be purchased in outdoor shops, like REI. Go to the Spot Messenger website for details. The only drawback on Spot is that you can't carryon a conversation, but only report progress or emergencies. The Delorme system allows texting, but is quite expensive.

Keep in mind that you will be meeting a lot of people on that trail, so it isn't likely you will be all alone in case of emergency.