Today I finally got to do a proper side-by-side comparison of an HP310
PNA and hx4705 PDA, each running SeeYou Mobile, under a bright sun and
in the glider cockpit.

In terms of screen performance under the Arizona sun, I could hardly
tell the difference between the two. If the HP310 was easier to read,
it was only slightly so.

In terms of software performance, the HP310 runs circles around the
hx4705, as one would expect. The release candidate version of SeeYou
Mobile (RC1) still has a little tweaking left to go but the crew at
Naviter has done an impressive job with it so far getting it to run on
Windows CE.

I still prefer touch screen systems and if and when a PNA comes along
with the brightness of the ClearNav or Ultimate, it will be very hard
to pass up.

I should also note that most of the popup menus on the 310 were nearly
impossible to read without good reading glasses. My computer readers
were not enough (the reader portion of my prescription bifocal tint
sunglasses).

If I were looking to upgrade from an existing HP PDA (39xx, 47xx) to a
PNA, I would hold off for the time being. The cost to do so would only
get you some software performance increase, and that's about it. I
would wait until a bigger difference in screen sunlight performance is
available.

If I were looking to establish a new PNA/PDA system in my glider, I
would certainly recommend the HP310. You can pick them up on ebay for
under $150. You'll spend more than that on the cradle, power and
serial-to-Bluetooth hardware.

~ted/2NO