I’d say you have two issues… 1. Coverage – which I think will be sporadic and not reliable 2. Battery Life – which is probably you main problem Even if you were able to get coverage occassionally during the hike, you will have very few opportunities along the JMT to recharge the device (since most are not AA, AAA battery powered – unless you have an ancient Palm device). I suppose you can always enter the data electronically and have it when you finish but that doesn’t do much to keep a journal updated on a daily basis (via the web). If it were me, I’d stick to paper and pen and mail the entries to someone at home that can post them on a website for you (like http://www.trailjournals.com). If it were a longer hike (like the AT, PCT, CDT) I might rethink this strategy but the miles on the JMT will go by quickly.
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