On an Android 6 device the app crashes with
11-28 12:53:26.067 3126-3126/dk.nordfalk.vuc_yttest E/AndroidRuntime: FATAL EXCEPTION: main
Process: dk.nordfalk.vuc_yttest, PID: 3126
java.lang.SecurityException: Missing android.permission.GET_ACCOUNTS
at android.os.Parcel.readException(Parcel.java:1599)
at android.os.Parcel.readException(Parcel.java:1552)
at com.google.android.gms.plus.internal.zzd$zza$zza.getAccountName(Unknown Source)
at com.google.android.gms.plus.internal.zze.getAccountName(Unknown Source)
at com.google.android.gms.internal.zzpn.getAccountName(Unknown Source)
at com.google.ytdl.UploadsListFragment.onConnected(UploadsListFragment.java:147)

This is because you need to request the permission at runtime.

Fix:

1. set your targetSdkVersion to 22 in your build.gradle, or
2. follow the steps described in https://developer.android.com/training/permissions/requesting.html

Read more here: http://stackoverflow.com/questions/33023674/android-6-getaccountname-missing-android-permission-get-accounts