refactor :

1. delete useless functions
2' init for adjust sdk

app/proguard-rules.pro

@@ -18,4 +18,9 @@
 
 # If you keep the line number information, uncomment this to
 # hide the original source file name.
-#-renamesourcefileattribute SourceFile
+#-renamesourcefileattribute SourceFile
+
+-keep class com.singular.sdk.** { *; }
+-keep public class com.android.installreferrer.** { *; }
+# Uncomment this line in case your are calling the 'revenue' function using the Google billing library
+#-keep public class com.android.billingclient.** { *; }