The app, once installed, ensures that you have the latest A-GPS data (which speeds up satellite lock times) and also, helpfully, checks for updated firmware, a nice touch. My iPhone4 managed 3hrs constant use running MotionX GPS with the Bad Elf GPS attached and pulling in map data over 3G.

Closest I've gotten is screenshotting the app when the accuracy is reasonably low, which obviously is not going to work for serious use.

I know what my choice would be, but obviously it’s a trade off of simplicity (and possible connectivity) versus GPS high performance and logging capabilities. The display is quite small and not always easy to see in some lighting conditions, however when the GPS is paired with its app over bluetooth these minor limitations seem irrelevant as any details can be easily seen in the more complete displays provided by the app. I now believe that GPS-based anchor alarm is dependent on logic to reject certain wrong fixes while alarming immediately on good fixes showing you adrift.

Given that it seems to have a fondness for thinking it's considerably off to one side when it's moving, and it loses the signal far more easily than other GPS units, I can't recommend it. Flex Mini is a mapping-grade GNSS that provides reliable and high-performance positional accuracy for tablets or smartphones. I have read the review of the Bad Elf iOS GPS dongle and it looks like what I need to be able to use CamerAlert on my iPad.I've also found that the communication between the app and the unit isn't reliable, which may be the crux of the problem. Flex Mini offers different levels of accuracy, depending on the receiver type, the correction method, and the environmental conditions. To make matters worse, I only learned I didn't get good data after I download the recording which was after I'd left the field.

The truly sad thing was that I was considering getting the Surveyor version of it to get greater accuracy until this experience helped me realized they won't stand behind their products. Truth be told, there's near to three pounds of fresh hops goes in every barrel of this treasured brew. I tried logging points directly on the device, and while the machine beeps to indicate a completed log, when I go back to view the logs, they show as zero points collected.When it is following the location well, it does it very well - but the iPad's own GPS isn't noticeably worse in most circumstances.