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en android 9 puedes activar los opciones por programmadores, y aqui hay un seccion energia. pro cada app puedes ver si android hace optimizaciones de energia. puedes ver si lo es deactivado por oruxmaps

[battery level 70% after 3h recording !!!!]

in short terms, i want to share these information, in case its of interest to somebody.
as a was disappointed with gps accuracy even under medium difficult conditions, i tested an external BT receiver.
here are my results, after tracking car trip, let it avtivated while shopping and for trailrunning.

external BT Device: NAVILOCK BT-821G
80 grams , 90 euro, changeable battery, no protection / IP / MIL cert

constellation A
HAFURY A7, cheap fone, very bad builtin gps capabilities, no protection, ca. 160gr, ca 16cm, android 9, Oruxmaps GP 7.5.8

coupling variant
worked very good and stable using the coupling method: mocked location provider with the app "Bluetooth GNSS - GPS, Galileo, GLONASS and BeiDou".
accuray (used in car): most of the time, 1m, you see on which side of the street you have been. (!)
stability BT connection: no cut offs
stability / accurcy of GPS signal: even in the building (light build rooftop), the signal was accurate (!)

coupling variant
direct coupling without mock/BT App.
which means: phone setting location is off (!), BT coupled to the external GPS device
this worked too


constellation B

motorola defy plus (2011) , Android 2.3, Oruxmaps 6.0.5
118 gram, 11cm, IP67, shockproof (tested for years, its unbreakable), removable battery
(rooted, underclocked etc.)

trailrunning, mediumdifficult conditions, direct coupling without additional app, GPS Setting in Phone is off, flight mode activated.

setting orux: timeinterval 4sec,distance interval 0m, accuracy limit 0m

recording time: 3h

battery level 70% before (it displays in 10% steps), battery level 70% after 3h recording !!!!

accuracy of the recorded track: very high. always 1meter accuracy, sometimes 2m.
update in a second test (2:30h recording time) the navilock was fixed on the belt of the rucksack, not on top of the shoulder but a little bit downwards. with this setup some more inaccuracies occurred, with this some recorded sections of the track have 2-3m offset and go in parallel. i suspect for real good accuracy the mount point of the device is very important, on (front) top of the shoulder in the former testcase produced a more exact result

in a small tunnel , it still had accuracy

a section where a came back after 1h both tracks are recorded without offset !!!!

noticed one inaccuracy: for 25km/3h after a change in direction, for about 200m, the accuracy was 5m.

the recorded trail 95% of the time sits exactly on the map's pathes, like it was drawed/prepared by hand an not have been recorded.

in every constellation: no cutoff of the BT connection, BT worked reliable (short distance), i didnt tested it with phone in the chest pocket (front of body) and the receiver in the bag (back).

to fulfill our (different) needs , even with expensive mobiles fones it gets complicated.

the main problem imho is that we have no sufficient test reports regarding the GPS capabilities / accuracy when used in the field or under "difficult" conditions.

for MTB, i suspect you also need a device which is not too big or too heavy. 

an option here is to use a cheap / protected phone together with am external bluetooth gps receiver

regarding the "navi" phone, it gets more complecated with these questions :
* does the navi/phone also needs to have a good camera
* do you want to use the navi/phone for calls in case of an emergency? for this, the SAR value should be (very) high and it has to support many communication freq.bands and dual sim so you can use 2 different communication networks.

regarding some testing reports and user feedback on amayon what i have read , this external BT GPS tracker seems to be "good" (better than Garmin and some other).
Note the sub 100$ price and the sub 100 gramm weight. this makes it feasable for hiking/running, mounted on top of the rucksack or similar good
position. drawback : it is not waterproof or similar IP rating

DE https://www.navilock.de/produkt/60324/merkmale.html

EN https://www.navilock.de/produkt/60324/merkmale.html?setLanguage=en

SP https://www.navilock.de/produkt/60324/merkmale.html?setLanguage=es


is it possible to run oruxmaps and record tracks with an external GPS/bluetooth tracker and let the location service in android deactivated ? (to save battery)

>>about xiaomi Mi8, my personal opinion is "stay away".

thank you, it is a frustrating topic. a analysis of the Mi8 resulted in  1-2 meters accuracy

see here:

https://www.mdpi.com/2079-9292/8/1/91/htm

with this in mind, chances are good to get an similar bad accuracy in spite of an GNSS dual freq. chipset with other devices :-(
currently i have a look on P30 and Pixel4 (both dual freq. GNSS).

the antenna is the problem, see here

https://www.sciencedirect.com/science/article/pii/S0263224120301718

here is a test of the badelf gnss surveyor. especially for running it is quite inaccurate. note that this was on flat terrain, in steep mountains or gorges, the accuracy will become even more worse

https://www.fulcrumapp.com/blog/gps-testing-with-bad-elf-gnss-surveyor/

for me it llooks like it makes no sense to use an external sensor. above performance is similar to my old motorola defy plus ( tuned settings).

study of the (much) increased power consumption of dual frequency gnss :

https://arxiv.org/pdf/1910.13041.pdf

or this one:

https://sxbluegps.com/products/survey-grade-gnss-receiver/

;-)

hi UH1169,

>>about external GNSS receiver

the prices goes up with these sort of hardware... i noticed intersing hardware from the following companies:
Bad Elf
Trimble https://geospatial.trimble.com/products-and-solutions/trimble-r1
EOS Arrow Series e.g. the flagship: https://www.agsgis.com/Eos-Arrow-Gold-Basic_p_17.html

i think about wheter its more accurate to use an simple external GPS/gnss bluetooth unit with a cheap smartfone/orux
that purchasing a 400eur+ dual freq. GNSS Smartfone and getting a similar accuracy like with your screenshots (mi8) ...

like
navilock gns 2000 or
garmin glo or
holux rcv 3000
...

maybe this is better, in case those BT trackers are fixed in a good position (on top of the rucksack or shoulder) it could be that the accuracy is better
as using a dual freq. gnss smartfone when it sits near the body in a e.g. chest pocket....

>>about xiaomi Mi8, my personal opinion is "stay away".

thank you, it is a frustrating topic. a analysis of the Mi8 resulted in  1-2 meters accuracy

see here:

https://www.mdpi.com/2079-9292/8/1/91/htm

with this in mind, chances are good to get an similar bad accuracy in spite of an GNSS dual freq. chipset with other devices :-(
currently i have a look on P30 and Pixel4 (both dual freq. GNSS).

thank you for your hints, the s8 came into my attention because of its size, ill check it out.

@ ineam: thank your very much, those professional level GIS devices from trimble led me into the GNSS world.. now i am getting close to the topic.

e,g, check this out:
https://www.mdpi.com/2079-9292/8/1/91/htm

already the introduction is very interesting

but as the intro suspects (study results), the antenna of the smartfones lead to fuzzy signals.
thus, i am thinking about an external GNSS bluetooth device which connects to oruxmaps.

however, GNSS capable devices are listed here:

https://developer.android.com/guide/topics/sensors/gnss

hello out there, since many years i am a kind of power user of orux maps. i use it for hiking and trailrunning in the mountains. i want to use a new phone and up to now was not able to find a suitable replacement for my old 2011 motorola defy plus 4 inch 120grams when it comes to recorded gps track accuracy. i spent large amounts of time trying out 2 new handies, analyzed different settings etc. but both had (different) problems. my last try was the cubot kingkong mini outdoor phone (4inch!). but its accuracy and stability of receive/hold the gps fix/position is poor. in spite of an displayed accuracy of 2-4meters in GPSStatus app the recorded track is not accurate, often 40m apart from the followed route then comes back again to be exact. often in spite of 2m accuracy the position still is somewhere and does not come back to the current location even when standing still for minutes.

i would be pleased if you share your phone which you use sucessful with orux.
my key requirements are small, light and robust gps signal processing even when the fone sits in an outer pocket on the chest, in a vertical orientation. i suspect some phones have a weak signal when they are not oriented horizontal (hold in hand) and when it sits near to the body so that some of the satelites are blocked.

thanks in advance

UPDATE/Answer:

inshort: see here which device offers "good" gpss capabilities:  https://developer.android.com/guide/topics/sensors/gnss   (but it does not reflect antenna related restrictions)

scroll down, table for a list of dual frequency gnss capable devices: https://medium.com/@sjbarbeau/tl-dr-dual-frequency-gnss-on-android-table-of-devices-9be4bbb83a7b
( https://medium.com/@sjbarbeau/dual-frequency-gnss-on-android-devices-152b8826e1c )

https://www.researchgate.net/publication/340392820_GNSS_code_and_carrier_phase_observations_of_a_Huawei_P30_smartphone_quality_assessment_and_centimeter-accurate_positioning

Prerequisite:

* applies to water protected / water proof smartphones



Scenario:

* using Orux while cycling and it starts to rain

* using Orux while Hiking/Trailrunning and it start to rain



when its raining it is difficult (hiking) or impossible (during cycling) to use orux because

the raindrops on the screen starting random functions.



currently no workaround available while cycling : i have to switch off orux.

during hiking a workaround is to use orux in a transparent plastic bag or using orux in

a rain protected corner, under the jacket or similar



Feature Request/Proposal:



possibiliy to switch off every command execution via display (menues, scrolling and so on)

and/but only zooming would be still possible via volumne buttons

and of course switch back to full display command mode (e.g. via both volume buttons at the same time or sth.)