Use supportLibVersion from ext.

android/build.gradle

@@ -3,7 +3,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.2.3'
+        classpath 'com.android.tools.build:gradle:2.3.3'
     }
 }
 
@@ -53,7 +53,7 @@ repositories {
 dependencies {
     //noinspection GradleDynamicVersion
     compile "com.facebook.react:react-native:${_reactNativeVersion}"
-    compile "com.android.support:support-v4:${_compileSdkVersion}.+"
+    compile "com.android.support:support-v4:${safeExtGet('supportLibVersion', '27.1.1')}"
     compile("com.github.bumptech.glide:glide:${_glideVersion}") {
         exclude group: "com.android.support"
     }

react-native-fast-image-example/android/build.gradle

@@ -47,5 +47,5 @@ ext {
     minSdkVersion = 16
     compileSdkVersion = 26
     targetSdkVersion = 26
-    supportLibVersion = "26.1.0"
+    supportLibVersion = "27.1.1"
 }