GPS Bluetooth - battery saver?

[Wojtas82]

Hi,
I was wondering if this setup will save my smartphone battery. I want to buy GPS Receiver that will be powered from my 7800mah PowerBank and communicate with the smartphone over bluetooth. Will this be a battery saver for smartphone? Did anyone use this kind of setup or similar? Any suggestions for GPS device? Thanks in advance!

[slarti76]

I tried two BT-GPS devices (Garmin Glo and GNS 2000), and returned them both.
Main reason was that the precision wasn't better (or even worse) than my Galaxy S4 itself. Especially annoying was that both transmitted a precision that was obviously nonsense (GNS 2000 almost always had <2m), whereas the S4's values are usually reasonably close to reality.
The second reason was that the battery saving effect was much less than I had hoped for. I was surprised to learn that the internal GPS alone doesn't draw that much anyway (put your phone into flight mode and do some GPS logging to check out). Especially when you got mobile network on anyway, the difference is hardly noticeable.
Of course, your experience may be different, especially depending on phone. But obviously, some more or less current high-end phone already has very low power consumption and good precision with internal GPS.

[ulmus]

Hi! I am using it that way. Holux rcv-3000 via BT and locus on my LG L9.
Normally with internal gps i can do about few hours with my mobile battery.
when i turn only BT without internal gps, and use it with holux i can record whole day.
But if i got external logger, it can work few days and you can only use locus to check position, so it drain battery as usual.
All recordings are done with logger. There is a small app to download gpx from logger into locus (if you want tracks).
I am always working that way... battery in my mobile last as it not use gps (if no recording with mobile but with logger of course, mobile/locus only for position check and download tracj later, logger can keep few days of recordings)

[Wojtas82]

Thanks a lot!

[jusc]

The internal GPS of some older tablets are not the best. So I used an external GPS receiver within the car behind the windscreen and got very good informations of position as co-driver.  On the other side, riding a bike my experiences are similar as slarti76 has made. In my case the precision was the same as with my phone, but I didn´t save much battery, And it´s a bit clumsy to handle.
I would say. sometimes the external GPS is usefull, but not in all cases.

[Menion]

may also confirm jusc information. Few years ago (+- 5) when I started with Locus and generally mobile devices with GPS, difference between BT GPS and internal GPS was really huge in terms on battery consumation and also precision.

Anyway last devices with support for Glonas satellites as well, has really good precising and made a great step compare to lets say 3-4 years old android devices. But seems that new BT GPS devices are still same quality as five years old. So generally I see no serious reason why to use BT GPS in case, you just wants better precision. In case of longer usage of device due to battery, I rather suggest small powerbank which is less expensive and has a lot wide range of usage. Just my two cents ...

[ulmus]

once more my two cents...
External BT logger is better if you want to have your track for sure. Using mobile is risky as we all know... interrupting phone calls, other applications etc... all of that can hang or shut down your mobile application, stop logging and so on... We all know that and i am sure that we met those things. In that case external gadget that do only one thing is the best solution for person who wants get his tracks for sure...
I agree that nowadays mobiles have great gps, but if you want only to play with gps and it does not matter if you loose your track then mobile with battery pack is the best choice.

[ohgood]

Hi,
I was wondering if this setup will save my smartphone battery. I want to buy GPS Receiver that will be powered from my 7800mah PowerBank and communicate with the smartphone over bluetooth. Will this be a battery saver for smartphone? Did anyone use this kind of setup or similar? Any suggestions for GPS device? Thanks in advance!

I've tracked for days without issue, while in airplane mode. the largest battery drain i've seen is, order highest to least:


1 poor cellular signal (if using online maps = a factor of 2-3 times higher drain)
2 display on
3 music/mp3
4 bluetooth (streaming to headset)
.
.
.
9 or 10 locus recording a track


The bluetooth devices are $50-100, and another failure point. I don't want to keep up with my cellphone battery, and I sure don't want to keep up with another devices battery along with it. Then there are the annoyances with bluetooth.... is it tracking now ? am I sure ? is it's battery dead ? etc


I can track for a solid day easily, in airplane mode, in the woods. that's longer than my body usually wants to keep moving. when i rest, i charge the phone.

[Menion]

Nice test!

9 or 10 locus recording a track

btw. that's what i wants to see .

[ulmus]

I would do only 2 tests in such case:

1. Internal GPS+Locus, airplane mode, BT off.
2. BT gps+locus, airplane mode, internal gps off.

in that case you can compare these two examples.

internal gps drain more than BT, that's all about it... i think.

[Wojtas82]

Never had any problems with Locus. I've been using it for over a year now, and track recording is always stable and solid. So I wouldn't say that using mobile is risky, especially when you have ultra stable software like Locus.

I made a test with my Xperia S + Power Bank PQI 7800 mah.
Screen was ON all the time, track recording on (I wasn't moving so maybe it would drain faster) 2G on, Data off, Wifi off. Screen brightness was set to 60%. I'm using offline maps. I got 13 hours of life after that power bank drained out. I still had 100% of battery phone so I could probably get another hour. With the screen off I would probably get few days without a charger (need to make test as well).

In this case I decided not to buy anything That's enough for me. I have power bank in a bag on my steering wheel with a cable to my Topeak phone holder on steering wheel. It's very easy to unplug a cable and take the phone with you when you go shopping for example.