Phone as GPS

[webcraft]

.
Making lists as part of planning a long voyage, I had included hand held GPS, battery operated as a backup position finder if all the boat electrics go down.

Then I thought - we will have at least two mobile phones on board, so no need for any other backup. They should be ab le to give GPS position anywhere, no?

Any comments?

- W

 

[anoccasionalyachtsman]

Dunno about very contemporary 'phones, but a few years ago they used to interrogate the nearest cell mast for its location and then use that to get a faster startup than patiently listening to satellites. Mid-ocean you'd therefore expect slower start than you're used to I think. Could be that newer 'phones don't need the help?

 

[jiris]

Unless the device has inbuilt satellite-based GPS, it calculates its position from the distance to mobile towers it has access to. So, it has to have access to at least 3 towers to delivery the coordinates.

 

[elton]

If it's a later Android phone, select Settings, then Location, and it should show you what type of location sources it has available and active, eg GPS, Wi-Fi and Mobile Networks.

 

[lpdsn]

Unless the device has inbuilt satellite-based GPS, it calculates its position from the distance to mobile towers it has access to. So, it has to have access to at least 3 towers to delivery the coordinates.

I don't even think they put the measurement of that into the 3G standard (i've certainly never got it in any info from a 3 or 4G cell but can't be bothered to trawl through the 3GPP specs tonight) so it is really just the 2G cells that can provide it. It can be very good in the right places but, as you say, is poor in areas with low cell density. When the EU introduced a requirement for locating emergency calls, which IIRC was to within 50m, it just wasn't sufficient, hence the reliance on GPS in smart phones of the last few years.

 

[RobbieW]

If all your electrics have gone down, how will you be recharging your phone ? The battery GPS has the advatage of being operable in isolation

 

[GHA]

If all your electrics have gone down, how will you be recharging your phone ? The battery GPS has the advatage of being operable in isolation

USB power pack and just turn one on for a few minutes couple times a day , batts would last week's without even needing a charge .

 

[duncan99210]

I’ve used both iPhones and iPads for position fixing offshore. They both provided the fix after a very short pause. You need to address the charging problem as Robbie says but phones do provide position fixing without needing to be connected to a network.

 

[Lon nan Gruagach]

Some phones do, some phones dont, some phones need a lot of loving and some phones.......
Here is the full skinny on phone location (android): https://developer.android.com/guide/topics/location/strategies.html


If possible it would be better to write or use an app that has a low power GPS strategy since the default is very high power demand. The assumption is that is you use GPS instead of the alternative faster, less accurate location services then power is a secondary issue.

 

[mbroom]

All my iPhones and Android phones over the past few years had a gps which enables a fix anywhere. Less battery life and more fragility, but perfectly usable and a better screen by far than most gps units.

 

[alteredoutlook]

remember to switch off the phone part of your phone to avoid it draining your battery too quickly in the vain attempt to find the masts.

 

[Bodach na mara]

I have used an Android tablet (Acer Iconia) for years as a chart plotter, loaded with MemoryMap app and their Admiralty charts along with Antares charts. There are also Navionics apps available.

For backup I have a USB power pack (Lidl). It certainly does not have features that people have show me on proper plotters but I am a simple man and probably could not use them anyway. I know that most things on my wife's smartphone are a mystery to me.

 

[Hoolie]

... ... and Wifi; that''s quite a drain too

 

[Bobc]

As an emergency backup, a phone with GPS is perfectly adequate. I would suggest that it's good to have 2 proper GPS devices on-board (one in the cockpit and the other at the chart table works well). Then the only time you would have to resort to the phone is in the event of both sets getting fried (lighting), or complete electrical failure (pretty unlikely).

As you say, if you take a fully charged powerpack, I can't see how that's not adequate for an emergency backup.

 

[[70521]]

.
Making lists as part of planning a long voyage, I had included hand held GPS, battery operated as a backup position finder if all the boat electrics go down.

Then I thought - we will have at least two mobile phones on board, so no need for any other backup. They should be ab le to give GPS position anywhere, no?

Any comments?

- W

Went to a Royal Institute of Navigation talk on GPS last night; a fascinating talk.

Personally, I'd have my handheld GPS and a mobile phone.

 

[Quandary]

.
Making lists as part of planning a long voyage,
Any comments?

- W

Yes, you will be taking 'Mountain' or whatever she is calling herself now, with you on this trip? it will be good for her to get out, to re-establish your intimacy and form a real bond. Spain should be suitably right wing though Trump ton would suit even better.
If you were to get lost at least you would be together and the rest of us would just have to try to try to carry on alone.

 

[jac]

The other alternative would be a HH DSC VHF radio with an inbuilt GPS. Depends what equipment you were planning on buying anyway of course as I wouldn't get one if you already had a HH but if you need to get a HH then get the additional functionality and kill 2 birds with 1 stone.

Still faces the challenge of charging but some have removable batteries and a slide in tray to fit AA batteries ( I know my SH does) so a blister packet of new batteries should cover that.

Not sure how long you want the back up to run as whether you go don the phone or the AA powered device you will eventually run out. I know there are USB power banks with small solar panels on them that might help to keep the phone going on a more permanent basis if you were thinking of passages lasting several days.

 

[wotayottie]

.
Making lists as part of planning a long voyage, I had included hand held GPS, battery operated as a backup position finder if all the boat electrics go down.

Then I thought - we will have at least two mobile phones on board, so no need for any other backup. They should be ab le to give GPS position anywhere, no?

Any comments?

- W

you'll need a bit of software to turn it into a lat and long, but yes, they all have gps these days.

but how long do phone batteries last? when you chat to your wife / mother or the SNP for hours?

a cheap hand held with a pack of batteries is a more reliable option.

P.S. If you are worried about that small a safety investment, then I will finally accept that you are scottish (if not yorkshire).

 

[RobbieW]

remember to switch off the phone part of your phone to avoid it draining your battery too quickly in the vain attempt to find the masts.

Setting the phone to airplane mode should deal with both wifi and phone function.

We seem to be straying from KISS here; if the OP already has a battery GPS but not a power pack then a few batteries is going to be cheaper, capisce ?

 

[Giblets]

Am currently going through the painful exercise of trying to educate 'er indoors regarding her iPhone battery usage. Apart from her turning off wireless and turning on mobile data when out and about and the reverse on arrival when near a wireless output I also had a look in the Location Services section in Settings and found that several of the apps show as using GPS constantly with the option to turn to Only When In Use or Never. All apps have been turned to OWIU so will await feedback. I have a feeling that this is changed to Constant whenever an app is updated. The clue is a constant small 45 degree arrow top right of the screen meaning GPS is active.