Update build.gradle

android/build.gradle

@@ -28,17 +28,22 @@ apply plugin: 'kotlin-kapt'
 
 android {
     compileSdkVersion 27
+    buildToolsVersion '27.0.3'+
+
 
     sourceSets {
         main.java.srcDirs += 'src/main/kotlin'
     }
     defaultConfig {
-        minSdkVersion 16
+        minSdkVersion 21
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
     lintOptions {
         disable 'InvalidPackage'
     }
+    
+    aaptOptions.cruncherEnabled = false
+    aaptOptions.useNewCruncher = false
 }
 
 dependencies {