IPad 3 wifi vs. iPad 3 4g

cocolos

Pre-takeoff checklist
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cocolos
hi I wanted to get foreflight for the iPad but I was curious would it be better to get the iPad with just wifi and buy an add-on for the gps or just get the iPad with 4g + gps? would the add-on be more accurate?
 
One of the advantages of having an external GPS is that it has a separate battery therefore both devices last longer. The disadvantage is that you have to carry an extra peace of equipment.
 
The internal GPS in the 4G iPad is more than accurate enough for WingX or ForeFlight. I have an external bluetooth GPS but never bother to use it since the internal one works good for me. It is also a pain having another device to have to keep charged and to keep up with. I can record my flight track in WingX and when I view it in Google Earth my take-off and landing track will be centerline of the runway. I typically get within 15' accuracy with the internal GPS.
 
I went Wifi but would probably do the 4G version next time. While external GPS is supposedly better, seems internal is good enough most of the time. I like having the internal in my Nexus 7 which leads me to use it more than the iPad, despite Garmin's software not being quite as good as FF.
 
I went Wifi but would probably do the 4G version next time. While external GPS is supposedly better, seems internal is good enough most of the time.

Same here
 
Internal GPS is good enough most of the time. However, if you're pinching pennies, I d suggest the WiFi-only model and get an ADS-B external unit that supplies weather! Yes, it's more expensive than the iPad with GPS, but you get weather, NOTAMs, PIREPS, etc. OTOH, if you have plenty of money, get the 4G (and GPS) built in and then buy the ADS-B unit too! There's no question that having GPS built into the unit adds a level of convenience.
 
I went Wifi but would probably do the 4G version next time.
Me too but only because (1) I find I'm using the iPad for much more than aviation and anticipate doing more with it the next time around and (2) I already have an external GPS, so I'd have the best of both worlds.
 
I went with the 3G model solely for the GPS and never bothered to activate a data plan. One advantage to having a data plan though is that you could have wind and weather updates enroute. I just pull my iPhone out if I need that functionality.
 
It's like buying a car, do you buy the cheapest model with no options or do you make the car fit your needs?

Spend the $100 an get the 4g option.
 
One of the advantages of having an external GPS is that it has a separate battery therefore both devices last longer. The disadvantage is that you have to carry an extra peace of equipment.

Care to supply a reference for that? It is doubtful that the GPS receiver in the iPad has a material impact on battery life. The cellular radio, on the other hand, can have a small impact (or probably imcremenatally larger impact if you're on Verizon), but you can turn cellular off and still use the GPS.

Even in a worst-case scenario, 8-9 hours on the iPad matches what you'd get with most external receivers.


JKG
 
The iPad with internal GPS is also nice for navigation when on the ground.
 
Care to supply a reference for that? It is doubtful that the GPS receiver in the iPad has a material impact on battery life. The cellular radio, on the other hand, can have a small impact (or probably imcremenatally larger impact if you're on Verizon), but you can turn cellular off and still use the GPS.

Even in a worst-case scenario, 8-9 hours on the iPad matches what you'd get with most external receivers.


JKG

It just makes sense. A turned on GPS uses power, if there is no GPS it does not use power.

Now the question is what uses more power an internal GPS or the bluetooth/wifi that you use to connect to the external GPS. Also you can connect the external GPS with a cable.
 
It just makes sense. A turned on GPS uses power, if there is no GPS it does not use power.

Now the question is what uses more power an internal GPS or the bluetooth/wifi that you use to connect to the external GPS. Also you can connect the external GPS with a cable.

I would think the internal GPS would use a fraction of the power of either BT or Wifi since it need not broadcast anything which is the power hog. Interesting question would be relative difference between inboard GPS vs. add-on Bad Elf GPS?
 
I went with the 3G model solely for the GPS and never bothered to activate a data plan. One advantage to having a data plan though is that you could have wind and weather updates enroute. I just pull my iPhone out if I need that functionality.

That's what I did, I seldom go anywhere that doesn't have wifi anymore! :D the 3G model's GPS works fine in flight without an external antenna or additional GPS. :D
 
if this is only for the cockpit, and you are going to get an ADS-B receiver anyway, then the wifi works.

However if you plan to use it as a multi purpose device, then the GPS inside the unit itself offers a lot more capability.

Also remember, the 4G one will sell for more when the time comes to upgrade, so while it cost more to buy, you will get some of that back on the back end.
 
I would think the internal GPS would use a fraction of the power of either BT or Wifi since it need not broadcast anything which is the power hog.

I notice in my phone anyway, that when I use GPS, the unit gets noticeably hotter then when I use wifi or 3G.

I also notice the battery drains a lot faster. One would think your conclusions are correct, but I don't think they are. Not sure why however.
 
When I get a chance, I want to compare the Garmin's 696's WAAS readings to those of built in GPS's for these pads. I haven't seen WAAS listed for the pads. Seems to me, that the most difference would be with GPS altitude. The external GPS would have the benefit of WAAS.
 
BT does not seem to use that much power due to range. . . .the transmitter that uses all the power is the 3G/4G antenna. I can have BT headphones on and watch a video on my iPad and after 2 hours I've still got 60% power left - if its just music not sure there is a noticably additional drain on the power . . .
 
I do not understand why do you need WAAS on the ipad? It's not like your going to be using the ipad as the primary means of navigation while flying an approach.
 
I do not understand why do you need WAAS on the ipad? It's not like your going to be using the ipad as the primary means of navigation while flying an approach.

Nope, you wouldn't be. However, I'm an altitude accuracy fanatic.....for different reasons. Other than that, the GPS & Garmin Pilot app on my Nexus 7 seems to do quite well, navigation wise.

L.Adamson
 
Nope, you wouldn't be. However, I'm an altitude accuracy fanatic.....for different reasons. Other than that, the GPS & Garmin Pilot app on my Nexus 7 seems to do quite well, navigation wise.

L.Adamson

I see.

I'd prefer to have WAAS for the ipad as well (actually I have it) but I don't think that I'd specifically pay for it if I already had a GPS without WAAS.
 
I notice in my phone anyway, that when I use GPS, the unit gets noticeably hotter then when I use wifi or 3G.

I also notice the battery drains a lot faster. One would think your conclusions are correct, but I don't think they are. Not sure why however.

I wonder how much of that is GPS and how much is the GPU since you're usually driving more pixels around when using a GPS app?
 
IMHO...don't even bother with external gps that connects physically on the docking port... very inconvenient location, in the way and begging to be broken.
 
I wonder how much of that is GPS and how much is the GPU since you're usually driving more pixels around when using a GPS app?

I don't think that's it.

A simple test, is to run Netflix for an hour (using GPU and wifi), and then run CloudAhoy for an hour with the screen off (using GPS), and see which one uses more battery.

If memory serves me, the use of the GPS will suffer more battery life, however I am not totally sure about that, and don't care enough to run the test :)
 
The cellular radio, on the other hand, can have a small impact (or probably imcremenatally larger impact if you're on Verizon), but you can turn cellular off and still use the GPS.

Just a point of clarity, the choice of carrier and modulation type, probably makes little difference in power consumed, unless you are always stationary and always a long way off from a VZ tower, and there's a T tower on your roof. Or vice-versa.

The transmitters in cellular devices are commanded by the network to variable power output levels by the network, as needed for the best reception of the device, measured by bit-error-rate, at the active receiver site.

As you move, the power level of your device will be going up and down in response to a bad or good signal path and the network defaults for keeping a single device from blocking multiple receivers.

This last one is what usually bites us in aircraft. The network commands the device to a low power output, and at the same time, the network is also busy trying to hand off the device from tower to tower while keeping the data flowing both ways.

We see it all the time here on the ground when we go to mountaintop radio facilities. Those sites can see virtually every cell tower in Metro Denver, which means, your cellular devices, go dead. The network protects its spectrum for low level users closer in.
 
IMHO...don't even bother with external gps that connects physically on the docking port... very inconvenient location, in the way and begging to be broken.

I couldn't disagree more. My iPad gets mounted inverted in RAM cradle with Bad Elf connected at the top. That puts it out of the way in the best positin for reception. And I don't have worry about the battery in my Dual GPS (which I also own.)
 
I notice in my phone anyway, that when I use GPS, the unit gets noticeably hotter then when I use wifi or 3G.

I also notice the battery drains a lot faster. One would think your conclusions are correct, but I don't think they are. Not sure why however.

GPS is only a receiver and should not drain the battery anywhere near what the 3G or 4G transmitters use or even the bluetooth. When you are using GPS, your navigation program is constantly performing calcs on the received data which is working the processor harder than most programs. The GPS receiver is not generating the heat and power drain, it's the processor chip. Regardless of whether you use the internal GPS or link to an external one, your processor will still be working like crazy processing all the data required of your navigation program. I think there is very little difference in battery drain using the internal GPS.
 
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I have a 3G + Wifi with no external GPS receiver. I've never lost GPS signal ever. When I got the IPad I had in my mind that I would get a Bad Elf or something, but it just hasn't been at all necessary so I've used that money for Avgas.

As far as battery life, my IPad will go hours and hours on one charge. I don't know what the battery life is, but if it's over 10 hours it wouldn't surprise me.

Good luck with your decision.
 
GPS is only a receiver and should not drain the battery anywhere near what the 3G or 4G transmitters use or even the bluetooth. When you are using GPS, your navigation program is constantly performing calcs on the received data which is working the processor harder than most programs. The GPS receiver is not generating the heat and power drain, it's the processor chip. Regardless of whether you use the internal GPS or link to an external one, your processor will still be working like crazy processing all the data required of your navigation program. I think there is very little difference in battery drain using the internal GPS.

That's not my experience. It has gotten better over the years but GPS still uses a lot of power. My old AT&T Tilt would eat up the battery like crazy when using the GPS. The iPhone 4 is a lot better as is the iPad. By comparison, enabling or disabling cellular data only makes a difference if you are constantly downloading and still not as much as GPS.
 
I couldn't disagree more. My iPad gets mounted inverted in RAM cradle with Bad Elf connected at the top. That puts it out of the way in the best positin for reception. And I don't have worry about the battery in my Dual GPS (which I also own.)

Agreed that sounds great. But, us non cradle people who need to lap it, or maybe a little clumsy with a peripheral hanging out like that....may break it. I have bad enough luck breaking my 1/8" headphone plugs. Even took out the jack on the back of my Mac.
 
Just a point of clarity, the choice of carrier and modulation type, probably makes little difference in power consumed, unless you are always stationary and always a long way off from a VZ tower, and there's a T tower on your roof. Or vice-versa.

That has not been my experience over the years. You're right that distance from the tower has an impact, but even at equidistant, CDMA in practice seems to suck down significantly more power than GSM. Verizon has struggled with this problem for years, with GSM carriers outclassing them handily in battery life. I will readily admit my bias against CDMA, though, because my experience with almost 10 years on Verizon was that battery life was lousy, voice quality was lousy (way too much compression when compared with TDMA/GSM carriers) and the capacity benefits of CDMA didn't always work as well as they were apparently supposed to, especially with data. I suppose it's a moot point, though, with everyone moving to LTE technology.

I haven't compared battery life of equivalent iPhones or iPads, for example, although I seem to have no problem reaching 9 hours or so of cellular data life out of the AT&T iPad 3. That's not too shabby regardless of whose network you're on.


JKG
 
Yeah, I can understand personal experience creating a bias, but I haven't seen any solid testing that shows one or the other to be a bigger battery-suck. Chipsets change, even the networks change...

CDMA has morphed significantly over time, and most folk's first experience with CDMA was around the time Qualcomm introduced the CDMA 2000 specifications. Today's CDMA doesn't even use much of that spec anymore.... Especially for data. Voice, still close...

So even changing what you're doing on a device can significantly impact the battery life. Both GSM and CDMA. (GSM phone doing 1xRTT out in the boonies will just heat up, blast through the battery, and die quick, for example...)

They're all fascinating. Whoever thought to just drop all the transmitters on the same frequency range and roll digital codes -- basically an "all interference, all the time" solution -- must have been thought quite a quack when they first proposed it in a lab somewhere. Heh.
 
My iPad is wifi only but I did try my iPhone with CloudAhoy.

The iPhone showed me making 2 "missed approaches" on touch and go landings. When I added the Bad Elf to the iPad, it tracked right done the runway. Airborne it did not seem to make a difference, at least one that was memorable or noticeable.

The Bad Elf doesn't seem to have much of an battery life effect but almost all of my flights are< 3-4 hours.

Cheers
 
Agreed that sounds great. But, us non cradle people who need to lap it, or maybe a little clumsy with a peripheral hanging out like that....may break it. I have bad enough luck breaking my 1/8" headphone plugs. Even took out the jack on the back of my Mac.

I don't want something as heavy as an iPad flying around my cockpit. When I kneeboard it (leg strap) I use a iPad cable extender to put the Bad Elf up on the panel.
 
I don't want something as heavy as an iPad flying around my cockpit. When I kneeboard it (leg strap) I use a iPad cable extender to put the Bad Elf up on the panel.

I gotta agree here. The iPad is in the yoke mount.

I've been bounced off the ceiling before. I really don't want an iPad to the chin.
 
That's not my experience. It has gotten better over the years but GPS still uses a lot of power. My old AT&T Tilt would eat up the battery like crazy when using the GPS. The iPhone 4 is a lot better as is the iPad. By comparison, enabling or disabling cellular data only makes a difference if you are constantly downloading and still not as much as GPS.


I've used Foreflight quite alot with the built in receiver and I've used the IPad for other things for lengthy periods of time and I have never noticed any difference in battery drain rate.

As Mick said, it is a RECEIVER.
 
Yeah, I can understand personal experience creating a bias, but I haven't seen any solid testing that shows one or the other to be a bigger battery-suck. Chipsets change, even the networks change...

CDMA has morphed significantly over time, and most folk's first experience with CDMA was around the time Qualcomm introduced the CDMA 2000 specifications. Today's CDMA doesn't even use much of that spec anymore.... Especially for data. Voice, still close...

So even changing what you're doing on a device can significantly impact the battery life. Both GSM and CDMA. (GSM phone doing 1xRTT out in the boonies will just heat up, blast through the battery, and die quick, for example...)

They're all fascinating. Whoever thought to just drop all the transmitters on the same frequency range and roll digital codes -- basically an "all interference, all the time" solution -- must have been thought quite a quack when they first proposed it in a lab somewhere. Heh.


Well they probably also thought Edison was a quack when he started multiplexing additional signals over telegraph lines. That's where that kind of thinking started.

In oil well logging, with a limited number of conductors going downhole to the instrumentation, it was amazing how many different ways we multiplexed signals INCLUDING a 3.5Hz carrier.:yikes: This was BEFORE the days of digitizing data and transmitting that. I'm sure that today they digitize everything, maybe even use a single signal conductor.
 
I plan on getting an ipad with 4g. Just wondering how much bandwidth you guys use when in flight and what data plans you have with your carrier.
 
I gotta agree here. The iPad is in the yoke mount.

I've been bounced off the ceiling before. I really don't want an iPad to the chin.

What do you recommend for a renter? I don't have a yoke, but a stick between my legs(no pun intended). Which also makes it damn near impossible to knee board it as well. Flying in a Piper Sport LSA. Not really sure what a good option is?
 
I plan on getting an ipad with 4g. Just wondering how much bandwidth you guys use when in flight and what data plans you have with your carrier.


I don't have a data plan for my IPad. The most remote, tiny terminal airports you can imagine have Wifi. Download weather before you leave and have the charts of interest downloaded to the IPad. You'll be good to go.

In my case I have an IPhone. If I ever get in a pinch where there's no wifi, I will tether my IPhone to get weather. I also have Foreflight on the IPhone. When you buy Foreflight the price includes both a license for the IPad and IPhone for the same price.

Don't tell anyone, but a few times I have checked weather on the IPhone with a 3G signal. I'm surprised how high you can still get a 3G signal.

Also, when I got my IPad I studied and researched various mounts before I flew with it in my lap. It works great and with no extra cost. When my wife gave me the IPad for Christmas she also gave me a leather cased, blue tooth keyboard. With the IPad folded out, the leather is on the bottom which makes it stick to my pants and not shift around.

Hope this helps.
 
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