diff --git a/build.gradle b/build.gradle
index 9d5855e..385f945 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,24 +1,25 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.2.50'
+    ext.kotlin_version = '1.2.61'
     ext.versions = [
-            'compileSdk': 28,
+            'compileSdk': 27,
             'minSdk': 16,
-            'targetSdk': 28,
+            'targetSdk': 27,
             'supportLibrary': '27.1.1',
-            'constraintLayout': '1.1.2',
-            'gson': '2.8.2',
+            'constraintLayout': '1.1.3',
+            'gson': '2.8.5',
             'okhttp': '3.10.0',
             'retrofit' : '2.4.0',
-            'rx2' : '2.0.2'
+            'rx2java' : '2.2.0',
+            'rx2android' : '2.1.0'
     ]
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.1.3'
+        classpath 'com.android.tools.build:gradle:3.1.4'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
diff --git a/studyplus-android-sdk2/build.gradle b/studyplus-android-sdk2/build.gradle
index fadcccb..28e966e 100644
--- a/studyplus-android-sdk2/build.gradle
+++ b/studyplus-android-sdk2/build.gradle
@@ -76,9 +76,8 @@ dependencies {
     implementation "com.squareup.retrofit2:converter-gson:${versions.retrofit}"
     testImplementation "com.squareup.retrofit2:retrofit-mock:${versions.retrofit}"
 
-
-    implementation "io.reactivex.rxjava2:rxandroid:${versions.rx2}"
-    implementation "io.reactivex.rxjava2:rxjava:${versions.rx2}"
+    implementation "io.reactivex.rxjava2:rxjava:${versions.rx2java}"
+    implementation "io.reactivex.rxjava2:rxandroid:${versions.rx2android}"
 
     testImplementation 'junit:junit:4.12'