diff --git a/apng_android/build.gradle b/apng_android/build.gradle
index 18f74e8c..5798d445 100644
--- a/apng_android/build.gradle
+++ b/apng_android/build.gradle
@@ -29,8 +29,8 @@ repositories {
 
 dependencies {
     testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'androidx.test:runner:1.2.0-alpha03'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0-alpha03'
+    androidTestImplementation 'androidx.test:runner:1.2.0-alpha05'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0-alpha05'
 
     api project(':apng')
     // 'api' に指定した依存関係はこのライブラリの利用者に公開されます
diff --git a/build.gradle b/build.gradle
index 5c89fea8..662bf5bf 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,8 +5,8 @@ buildscript {
     ext.androidx_version= '1.0.0'
     ext.appcompat_version='1.0.2'
 
-    ext.kotlin_version = '1.3.30'
-    ext.kotlinx_coroutines_version = '1.2.0'
+    ext.kotlin_version = '1.3.31'
+    ext.kotlinx_coroutines_version = '1.2.1'
     ext.anko_version='0.10.8'
 
     repositories {
@@ -16,7 +16,7 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.2'
+        classpath 'com.android.tools.build:gradle:3.4.0'
         classpath 'com.google.gms:google-services:4.2.0'
         // https://android-developers.googleblog.com/2018/05/announcing-new-sdk-versioning.html では
         // com.google.gms:google-services:3.3.0 以降を使うように書いてあるんだけど、3.3.0にするとGradle sync に失敗する。
diff --git a/gradle.properties b/gradle.properties
index 9742482e..5ec543d3 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -9,7 +9,7 @@
 
 # Specifies the JVM arguments used for the daemon process.
 # The setting is particularly useful for tweaking memory settings.
-org.gradle.jvmargs=-Xmx4096m
+org.gradle.jvmargs=-Xmx4g -XX:MaxMetaspaceSize=512m -XX:+HeapDumpOnOutOfMemoryError -Dfile.encoding=UTF-8
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 3d09a315..d7cf1b76 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Tue Mar 27 11:23:31 JST 2018
+#Fri May 03 11:34:20 JST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.2-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip