Please don't regard him as an "expert"; he's getting quite old and thinks that "fadiddling fumble-putz" is a more accurate description.

My iPhone4 managed 3hrs constant use running MotionX GPS with the Bad Elf GPS attached and pulling in map data over 3G. General aviation pilots: use your iPhone or iPod touch as a backup for charts on your iPad, switching instantly if needed without re-pairing or connecting. Pull up a sturdy chair, let's fill up yer best flagon with the season's finest natural ale, and I'll tell you a dark tale of elf and woe. Their feedback and requirements have driven our team to build the most powerful GNSS receivers that are also affordable, accurate, and intuitive.Even with the accuracy issues, this is the best unit I’ve ever used for for cost, size, and usability. Going up series of hairpin bends on a road, the other trackers would be absolutely bang on within the limits of the recording frequency; the Bad Elf was all over the place, even going in circles in some places. Dual is out with an XGPS160 model that has many of the Bad Elf Pro features like logging and high refresh rates, and it will work with both iOS and Android devices. What’s particularly neat is how easily you can access and manage your track data from the iThing app. The fist thing is battery life, which is non-existent on any device with built-in GPS running, second is flexibility because you can geotag multiple cameras with one GPS when people are with you.

We plan to add support for all non-iOS devices (PC, Mac, Android, etc) over Bluetooth SPP profile in the next 1-2 app/firmware updates. I don’t think you’ll be disappointed, John, and I heard this today from one of the principal Elves: “Still lots of improvements and new features to roll out over the coming months, but the feedback from early adopters has been very positive. Because most of my tracks are recorded in a car, and they can be overlaid onto maps to see how well the tracks match with the roads.I tested the dongle with Garmin, TomTom, NDrive and Memory-Map on an iPod Touch and all worked perfectly. Thanks Darren and Sean16v for your help - I think I'll be going for the Bad Elf iOS GPS dongle then.