Visibility of countryborder

I am now using the open street map.

Hi,
I'm sorry but the country border are visible in OSM map (Map > Online > OSM Other > Classic) also you can see the border in default LoMaps or any other map. Or what's your goal, please?
Thanks, Petr

My goal is to see the border clearly and clearly. so that when planning I can see in which country I am working.

And from a certain zoom level I can see the countries well.

I can understand. Well there are following possibilities:
- customize the theme as mentioned earlier
- download the borders for example from https://www.naturalearthdata.com/downloads/10m-cultural-vectors/10m-admin-0-boundary-lines/
- convert the SHP to GPX or KML (for example in QGIS)
- import the file into Locus Map

BTW: our app Locus GIS can import the SHP directly. https://play.google.com/store/apps/details?id=menion.android.locus.gis

EDIT:
Maybe the ideal option is WMS service with country border ( you can add it via Map Manager > WMS/WMTS tab > PLUS > add WMS link and set the URL https://maps.nccs.nasa.gov/mapping/services/base_layers/esri_world_administrative_divisions/MapServer/WMSServer

If you need precise boundaries please search the WMS or data services of your national geo institute

Allright tyhanks for the information, this sound as a very nice project for me. I going to work with it.

EDIT: I have already a QGIS project with the boarders.

I want to let you know that it worked with the *.kml file.

The *.gpx file does not work Qgis could not convert my polygon to the *.gpx format.

By the way, is it also possible to adjust the formatting of a number of lines/tracks at the same time (slightly thicker line/track)

I'm sorry, I'm not very familiar with QGIS, but I assumed it supports GPX files as well.

Could you please provide a bit more detail about your last question?
(By the way, if it's not related to country boundaries, it might be better to start a new topic.)

QGIS can handle GPX files, I think only lines and points. But I get an error bij making of mijn boarders. But never mind. It is working with KLZ.

For Editing of the multiple lines , I can make a new topic.

To draw borders yourself is a funny idea. But of course not the intention. Because that takes too much time.

Edit okay