error at compile 'com.android.support:appcompat-v7:+'
All com.android.support libraries must use the exact same version specification (mixing versions can lead to runtime crashes). Found versions 26.0.0-alpha1, 25.3.1, 23.2.0. Examples include com.android.support:animated-vector-drawable:26.0.0-alpha1 and com.android.support:cardview-v7:25.3.1 less... (Ctrl+F1) -------------- solution: compile( 'com.android.support:appcompat-v7:25.3.1' ) { exclude module : 'support-v4' }