the quartz-beta samples returns repository not found when I am cloning it in android studio.
whats the problem ?
The problem is with your url, you don't clone a branch you clone the repository so the url for a direct clone (no fork) is https://github.com/Esri/arcgis-runtime-samples-android.git. Then you switch to the branch you want to work from. I do suggest for fork the repository first and then clone your fork as described in the README and here.
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