[Paul_Sengupta]

Ah.

Load and launch one of these apps and leave your phone outside for a few mins, see what happens.

https://play.google.com/store/apps/details?id=com.eclipsim.gpsstatus2

https://play.google.com/store/apps/details?id=com.chartcross.gpstest

Have a look what satellites it receives. Then try Sky Demon!

[PeteSpencer]

While I use a yoke mounted iPad Mini 4 for SD navigation, I also have my iPhone 7 S (gps equipped) suction mounted alongside.

It displays , Bluetoothed from iPad , a full screen ‘virtual radar ‘ feed from Sky Echo via SD .

A separate ear bud Bluetoothed in my left earhole carries the audible warnings)

Works well.

However my Fpl and pilot log on SD is running independently in the background on the iPhone 7, ready at the flick of a switch, to be displayed should anything befall the iPad.

(Which as a matter of interest hasn’t overheated for three years following the simple advice steps published then by stevelup. )

[CloudHound]

Can you remind us of those wise words?

[patowalker]

Even without a SIM a mobile will search for mobile towers and locate itself

How does that work on a wi-fi only tablet? The specs do not mention A-GPS.

[Flyin'Dutch']

Even without a SIM a mobile will search for mobile towers and locate itself

How does that work on a wi-fi only tablet? The specs do not mention A-GPS.

It doesn't.

But a wifi only table is not a mobile, is it?

[JAFO]

I often make phone calls whilst airborne using the Bluetooth connection to my fantastic SEHT headset.

There again I'm generally around 1500' travelling at 70 kts!

Still not legal, though.

[patowalker]

Even without a SIM a mobile will search for mobile towers and locate itself

How does that work on a wi-fi only tablet? The specs do not mention A-GPS.

It doesn't.

But a wifi only table is not a mobile, is it?

Silly me. I thought you were responding to my comment on tablets without a SIM. It is a wonder I can locate myself.

[Flyin'Dutch']

How does that work on a wi-fi only tablet? The specs do not mention A-GPS.

It doesn't.

But a wifi only table is not a mobile, is it?

Silly me. I thought you were responding to my comment on tablets without a SIM. It is a wonder I can locate myself.

[Paul_Sengupta]

Also just because they don't have a sim card in them, doesn't mean they are the Wifi only version! It could have the sim slot but not the sim...

[riverrock]

Also not to be confused with iPads, in which the non-SIM models also don't include GPS receivers (almost all android tablets have separate internal GPS recievers).

[Rob P]

I often make phone calls whilst airborne.

FFS why?

Isn't the point of going flying to get away from all that?

Or is this some bizarre one-upmanship at people who have said "I'm on the train" when you've phoned them?

Rob P

[patowalker]

Also just because they don't have a sim card in them, doesn't mean they are the Wifi only version! It could have the sim slot but not the sim...

No chance of that, at the prices I am willing to pay.

[JAFO]

I often make phone calls whilst airborne.

FFS why?

Isn't the point of going flying to get away from all that?

Or is this some bizarre one-upmanship at people who have said "I'm on the train" when you've phoned them?

As long as you don't say "Just a minute, I'm going into a tunnel."

[PeteSpencer]

Can you remind us of those wise words?

Sure: Repeated with acknowledgment to Stevelup:

1) turn down brightness off 100% (I use 75%ish)
2) Don' t use power from a/c, use iPad's internal battery instead

(Charging in use generates heat): I have the power lead in place when flying (It's integral to my Brodit iPad mount) but only plug in if I see battery level dropping in flight.

Again acks to s-lup.

[tripacer]

The GPS receiver in your phone is independent of having a phone signal.

Only partly true. Nearly all modern phones use the cellular signal for assistance, primarily to get a location fix in the first place (ore more precisely acquire the signal from each satellite). Once you have acquired the signals, it moves into tracking mode, when cellular data is not required. Without cellular data, it can download the required data from the GPS signal itself, but this is slow and will take 5-6 minutes for the complete set of data. You may find on standalone GPS receivers that they acquire faster if they have been used recently (last couple of weeks) and faster still if they have been used in the last day or two.

For Android (no idea about ios) an app can separetly choose "coarse" location (cellular network based location) and "fine" location (sat nav). Fine uses more battery power, but I expect that SkyDemon and other aviation apps use only fine (as coarse can be thousands of metres out in extreme cases) but many apps use both. As coarse is usually faster, this is why on Google maps etc, you may first see the often-inaccurate coarse location, and then a much better fine location as soon as it synchs to the satellites (GPS, Glonass, Galileo, BeiDou etc)