For an emergency cell phone to carry outdoors, I'd consider looking into the SpareOne Emergency Phone.



Touted features include:
  • Talk-through, waterproof, floatable packaging
  • Powered provided by a single AA battery (comes with 15 year lithium)
  • Lightweight & slim design (75 grams)
  • LED Torchlight (up to 24 hours of continuous light)

I don't know much more than what is on the website, but it seems worth looking into.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen