Gradle: switch from "javac and dex" to "jack and jill" (experimental) - more about that https://www.saikoa.com/blog/the_upcoming_jack_and_jill_compilers_in_android

mobile/com.sap.sailing.racecommittee.app/build.gradle

@@ -13,7 +13,7 @@ android {
         targetSdkVersion 21
         versionCode verCode
         versionName "$verCode - Laser"
-        useJack false
+        useJack true
     }
 
     sourceSets {
@@ -30,8 +30,10 @@ android {
             applicationIdSuffix ".dev"
             versionNameSuffix ".debug"
 
+/*
             minifyEnabled true
             proguardFiles getDefaultProguardFile("proguard-android.txt"), "proguard-project.txt", "../proguard-mobile.txt"
+*/
         }
 
         release {