Any good, bad, or interesting experiences with third-party GPS on your iPad

[computerdoc]

With the discontinuation of the 740 I’m preparing for that inevitable day with my 740 dies and I can’t get a new one.
As I mentioned in another thread, I use my iPad as my back up iFly GPS, and it is notoriously, inaccurate, reporting altitude, likely due to no built-in WAAS in its internal GPS.
I see third party Linkable GPS WAAS enables units.…Bad Elf.

anybody have experience with those they would report?
(And maybe in particular have you noted accurate altitude reports?)

 

[Nitrodawg]

Prior to purchasing my 740b I used an ipad mini (no phone capability model), Foreflight, and a Dual Electronics GPS unit. This combination always got me where I wanted to go. As far as altitude is concerned, I have never seen complete agreement between the altimeters, both mechanical and electronic, and gps supplied elevation. I am under the impression that gps altitude is a calculated number and altimeters are affected by the barometric setting and instrument tolerance, which makes unlikely that there would be complete agreement.

 

[Gatormyk]

With the discontinuation of the 740 I’m preparing for that inevitable day with my 740 dies and I can’t get a new one.
As I mentioned in another thread, I use my iPad as my back up iFly GPS, and it is notoriously, inaccurate, reporting altitude, likely due to no built-in WAAS in its internal GPS.
I see third party Linkable GPS WAAS enables units.…Bad Elf.

anybody have experience with those they would report?
(And maybe in particular have you noted accurate altitude reports?)

Unfortunately, I don't have any experience with the Bad Elf units. I do have experience with other units if you wish to read on.

I have used Dual GPS devices with much success. I have used the Dual XGPS 150 and the Dual XGPS 160. These connect via Bluetooth. These units only provide WAAS GPS services. WAAS GPS devices will provide GPS altitude which is accurate but I have seen that they will differ from the altitude reported by your altimeter. The 150 connects to a single device where the 160 will connect up to 5 devices. I believe Dual still manufactures and sells these. I actually have both devices (used) and am willing to sell them.

However, if you are open to other options that also provide ADS-B In services as well as WAAS GPS, I have used a Stratux that I built that provides WAAS GPS and ADS-B In for traffic and weather and AHRS as optional. Connectivity is via WiFi. It worked great. I have since moved to a Stratus 3, which may be a better option if you are not comfortable tinkering with building your own solution. It provides all of the same services I listed with the Stratux and AHRS is built in, but you can opt not to use it. It also connects via WiFi.

The build-it-yourself Stratux used to cost around $200 to build but I think current prices of the Raspberry Pi single board computers are a bit pricey right now. A Stratus 3 will set you back about $750 but in my opinion, is worth the cost for the services it provides to your moving map software.

 

[computerdoc]

Prior to purchasing my 740b I used an ipad mini (no phone capability model), Foreflight, and a Dual Electronics GPS unit. This combination always got me where I wanted to go. As far as altitude is concerned, I have never seen complete agreement between the altimeters, both mechanical and electronic, and gps supplied elevation. I am under the impression that gps altitude is a calculated number and altimeters are affected by the barometric setting and instrument tolerance, which makes unlikely that there would be complete agreement.

Hi Nitro…

Short version of a long reply:
When the GPS is WAAS enabled, as it is in the 740, it is incredibly accurate in reporting altitude.
(as evidenced, by among other things, the following: when, on the ground at an airport it reports altitude within a few feet of the official altitude.)

Yes a WAAS GPS well disagree often with the altimeter adjusted to the metric pressure reports.
The GPS will be more accurate when they disagree.

 

[Cobra]

I would suggest that your priorities are misaligned. In the US, all reported altitudes are still pressure altitudes, so GPS accuracy is a moot point when dealing with ATC or nearby traffic.

The only reason you'd be concerned about altitude inaccuracy in a portable device is if you're NOT using it with an ADSB-in receiver (which would solve your WAAS concerns). But the difference in accuracy is small enough that in practice there's no issue. The only function your device's built-in altitude would be used for is terrain / obstacle alerting. And since you can set terrain alerts to start going off when you're projected to come within 1000', a few 10s or even 100s of feet of inaccuracy is not that big a deal. Obstacle alerting only comes into play within 400', so maybe that's more significant, but generally it's very easy to fly well above obstacles so they're not as big an issue.

But if you're not using your device to get traffic and weather in the cockpit, then you're missing out on the largest benefit of having such a device. Altitude accuracy is small potatoes compared to weather and traffic.

So get an ADSB-in receiver and solve your (not so important) altitude accuracy issues, plus get all the most important benefits of having a portable device in the cockpit. Problem(s) solved.

 

[Don Norris]

I use a Garmin Glo GPS receiver to provide GPS to the tablet (Samsung Tab A at this time). We;ve had it about 10 years and never had a problem across the three tablets it's been used with.
We also have a Stratux for ADSB in, but since it lives under the panel, I didn't add GPS to it.

 

[Nitrodawg]

With the discontinuation of the 740 I’m preparing for that inevitable day with my 740 dies and I can’t get a new one.
As I mentioned in another thread, I use my iPad as my back up iFly GPS, and it is notoriously, inaccurate, reporting altitude, likely due to no built-in WAAS in its internal GPS.
I see third party Linkable GPS WAAS enables units.…Bad Elf.

anybody have experience with those they would report?
(And maybe in particular have you noted accurate altitude reports?)

Yes, I understand that ipads are not that accurate on their own, that's why I noted my use of the Dual GPS ( model XGPS160 ). Yes, I understand that WAAS enabled devices are very accurate, also why I use the Dual GPS. What I apparently didn't understand is that you were only interested in the Bad Elf devices. Can't help ya there.

 

[tbouchertx]

I use the Bad Elf Pro +. I have had some trials and tribulations with the use of it with IFly EFB. I just used it today on a 3 plus hour flight and it worked flawlessly. No issues. I use it at work when middle of the night over the ocean. Despite being on a flight deck with heated windows, it works flawlessly with work EFB, just not with Ifly EFB. That’s OK bcs the Ifly is my GA EFB. Worked beautiful.