====== None, inaccurate or wrong GPS location and elevation ======

----
<WRAP center round important>
**Important!** 

Get Locus Map permission for **all-time access to location** and **exclude it from all means of battery optimization** so that the app can run and access location data in the background. Instructions on how to do it are summed up **[[manual:faq:gps_lost_fix_android6|here]]** or **[[https://dontkillmyapp.com/|here]]**.
</WRAP>

Locus Map processes location and elevation gain from the data it receives from **your phone GPS** and other location/orientation sensors. If the data is incorrect or contains deviations, the resulting location fix and elevation gain are incorrect. Locus Map, however, offers a few methods for limiting these deviations.
===== No location at all =====
There are a few reasons why the app might not show your location on the map:
==== Access to GNSS data is turned off in Locus Map ====
  * the GPS indicator is white:\\ {{ :manual:faq:badgps01.jpg?nolink |}}
  * tap it and then tap either the skyplot or the button to **turn on getting location**:\\ {{ :manual:faq:badgps02.jpg?nolink |}}

==== The phone's GNSS is turned off ====
  * the GPS indicator is orange, there is a badge on the centering button and a warning emerges:\\ {{ :manual:faq:badgps03.jpg?nolink |}}
  * **turn on your phone's GNSS**:\\ {{ :manual:faq:badgps06.jpg?nolink |}}

==== No location permission for Locus Map ====
  * the GPS indicator is white and tapping the centering button or the GPS skyplot displays a warning:\\ {{ :manual:faq:badgps04.jpg?nolink |}}
  * in system settings, allow Locus Map access to precise location **all the time**:\\ {{ :manual:faq:badgps05.jpg?nolink |}}

===== Light deviations =====

**Open Locus Map settings > GPS&sensors and set the following**

  * Location filter > select **medium or heavier filter**
  * Google Services assisted location > **turn it ON** (or OFF, it depends on your device)
  * Altitude manager > settings tab > SRTM data - select **Optimize GPS values**
  * Altitude manager > settings tab > Pressure sensor > **turn ON** (if available)
  * Altitude manager > settings tab > Altitude filter - select **medium or heavier filter**

===== Stronger deviations =====
Sometimes it happens that the GPS chip is malfunctioning or terrain/weather conditions are so demanding that elevation data is incorrect even after applying the measures mentioned above. Then try the following:
   * Open Locus Map settings > GPS&sensors > Altitude manager > settings tab > SRTM data - select **Replace GPS values** - this option calculates elevation gain from **offline elevation data** without using GPS

==== Custom altitude threshold ====
Those who are still unsatisfied with the result can change the elevation gain calculation by applying a custom altitude threshold:
  * open **[[manual:advanced:customization:config#expert_settings|Expert settings]]** > Customize altitude threshold > enable it
  * open a track or route detail > select **Edit** from the bottom menu
  * change altitude threshold with the slider\\ {{ :manual:faq:threshold.jpg?nolink |}}

<WRAP center round info>
By default, the altitude threshold in the app is not fixed. It is based on the source of the elevation. App decides by following the check (in this order):
  * if you use a pressure sensor, the app sets the threshold to "2"
  * if you use elevation data (enabled in "[[..:user_guide:tools:altitude|Altitude manager]]"), the threshold is set to "3"
  * if you have Android 12+, the threshold is set to "5"
  * otherwise it is set to "10"
  * generally, the default value is "5". It should be set to all imported tracks or to old tracks recorded before this parameter was introduced
</WRAP>