Switched from Volley to RetroFit + OkHttp for performance and simplicity

app/proguard-rules.pro

@@ -16,11 +16,13 @@
 #   public *;
 #}
 
+# RetroFit
+-dontwarn retrofit.**
+-keep class retrofit.** { *; }
+-keepattributes Signature
+-keepattributes Exceptions
+
 -keep class !android.support.v7.internal.view.menu.**,** {*;}
--keep public class * implements com.bumptech.glide.module.GlideModule
--keep public enum com.bumptech.glide.load.resource.bitmap.ImageHeaderParser$** {
-    **[] $VALUES;
-    public *;
-}
+
 -dontwarn
 -ignorewarnings