I always bring 2 navigators with me. Have an older DroidX android and a new android both running XCSoar latest stable version. I found the #1 problem is the GPS view of the sky. I always get a few short dropouts if I'm not using my external Bluetooth GPS which is mounted high and as clear a view as possible. Also I've noticed with the external gps that I seem to get better response updates especially while thermaling. It's less likely to lag.. Even my new Galaxy Note2 will hickup if in my lap during flight. Also GPS must be at least 1 foot apart if you're using two. Also fashioned a few very small 12 volt batteries to plug in the Androids. I only rent gliders.

I think XCSoar is amazing. It's very flexible but with that comes complexity. If you don't do your homework and use a checklist for setup you will be sorry. I can't recall any recent lookups freezes whatever.

Garmin Pilot, the power plane app is a great backup too. Sectionals, weather radar, forecast winds aloft all on the sectional. Great for studying a possible landout airport that is unfamiliar. No freeze ups with that app either. Need to be low to get cell.

I also agree some of those old iPaqs still have the best direct sun readability. Under a cloud the Android Oudie etc are a match. I had some freezes with iPaqs running SeeYou Mobile. Even my one year old Colibri II gave me an invalid IGC. I missed a few firmware updates that corrected bugs.

I use cheap, clip on, hinged pola sunglasses. In full sun I slide them up on my regular glasses a bit so that I can see under them when looking at the Android, but get full sunglasses view of everything out the canopy. This helps readability a lot.

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