diff --git a/.travis.yml b/.travis.yml
index 55056bf..9fba70e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,8 +3,8 @@ jdk: oraclejdk8
 
 env:
   global:
-    - ANDROID_API=28
-    - ANDROID_BUILD_TOOLS=28.0.3
+    - ANDROID_API=29
+    - ANDROID_BUILD_TOOLS=29.0.2
     - EMULATOR_API=21
 
 android:
@@ -22,7 +22,7 @@ android:
     - '.+'
 
 before_install:
-  - yes | sdkmanager "platforms;android-28"
+  - yes | sdkmanager "platforms;android-$ANDROID_API"
 
 before_cache:
   - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
diff --git a/app/build.gradle b/app/build.gradle
index 7d1e5db..cf44641 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,13 +1,13 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 28
-    buildToolsVersion "28.0.3"
+    compileSdkVersion 29
+    buildToolsVersion "29.0.2"
 
     defaultConfig {
         applicationId "com.github.javiersantos.piracychecker.demo"
         minSdkVersion 14
-        targetSdkVersion 28
+        targetSdkVersion 29
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
@@ -39,7 +39,7 @@ dependencies {
     implementation project(':library')
 
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
-    implementation 'androidx.appcompat:appcompat:1.0.0'
+    implementation 'androidx.appcompat:appcompat:1.1.0'
     implementation 'com.google.android.material:material:1.0.0'
     implementation 'androidx.cardview:cardview:1.0.0'
 
@@ -52,4 +52,4 @@ dependencies {
     androidTestImplementation('androidx.test.espresso:espresso-core:3.1.0', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-}
\ No newline at end of file
+}
diff --git a/build.gradle b/build.gradle
index 2e686f2..6397d07 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,14 +1,14 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.3.0'
+    ext.kotlin_version = '1.3.50'
     repositories {
         jcenter()
         google()
         maven { url 'https://jitpack.io' }
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.1'
+        classpath 'com.android.tools.build:gradle:3.5.0'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index f9d8c27..77e570b 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
-#Mon Jan 8 01:52:21 CET 2018
+#Tue Sep 10 22:40:11 COT 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.6-all.zip
diff --git a/library/build.gradle b/library/build.gradle
index 023a61a..a941fe1 100644
--- a/library/build.gradle
+++ b/library/build.gradle
@@ -4,14 +4,14 @@ apply plugin: 'com.github.dcendents.android-maven'
 group = 'com.github.javiersantos'
 
 android {
-    compileSdkVersion 28
-    buildToolsVersion "28.0.3"
+    compileSdkVersion 29
+    buildToolsVersion "29.0.2"
 
     defaultConfig {
         minSdkVersion 14
-        targetSdkVersion 28
-        versionCode 125
-        versionName "1.2.5"
+        targetSdkVersion 29
+        versionCode 126
+        versionName "1.2.6"
         consumerProguardFiles 'proguard-rules.pro'
     }
     buildTypes {
@@ -25,11 +25,12 @@ android {
 
 dependencies {
     api fileTree(dir: 'libs', include: ['*.jar'])
-    implementation 'androidx.appcompat:appcompat:1.0.0'
+    implementation 'androidx.appcompat:appcompat:1.1.0'
+    implementation 'androidx.preference:preference:1.1.0'
     implementation 'com.google.android.material:material:1.0.0'
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
 }
 
 repositories {
     mavenCentral()
-}
\ No newline at end of file
+}
diff --git a/library/src/main/java/com/github/javiersantos/piracychecker/utils/SaltUtils.kt b/library/src/main/java/com/github/javiersantos/piracychecker/utils/SaltUtils.kt
index 8e0a3c7..dde338e 100644
--- a/library/src/main/java/com/github/javiersantos/piracychecker/utils/SaltUtils.kt
+++ b/library/src/main/java/com/github/javiersantos/piracychecker/utils/SaltUtils.kt
@@ -1,7 +1,7 @@
 package com.github.javiersantos.piracychecker.utils
 
 import android.content.Context
-import android.preference.PreferenceManager
+import androidx.preference.PreferenceManager
 import java.util.Random
 
 /**
@@ -16,10 +16,8 @@ internal object SaltUtils {
             val sb = StringBuilder()
             mSalt?.let {
                 for (i in it.indices) {
-                    if (i > 0) {
-                        sb.append(" ")
-                    }
-                    sb.append(java.lang.Byte.toString(it[i]))
+                    if (i > 0) sb.append(" ")
+                    sb.append(it[i].toString())
                 }
             }
             return sb.toString()
@@ -34,10 +32,8 @@ internal object SaltUtils {
             }
         }
         context ?: return
-        val saltStr = saltString
         PreferenceManager.getDefaultSharedPreferences(context)
-            .edit().putString(KEY_SALT, saltStr)
-            .apply()
+            .edit().putString(KEY_SALT, saltString).apply()
     }
     
     private fun bytesFromString(string: String): ByteArray {
@@ -54,20 +50,15 @@ internal object SaltUtils {
             mSalt = context?.let {
                 try {
                     val prefs = PreferenceManager.getDefaultSharedPreferences(context)
-                    if (prefs.contains(
-                            KEY_SALT)) {
-                        bytesFromString(
-                            prefs.getString(
-                                KEY_SALT,
-                                null))
+                    if (prefs.contains(KEY_SALT)) {
+                        val saltFromPrefs = prefs.getString(KEY_SALT, null)
+                        saltFromPrefs?.let { bytesFromString(it) }
                     } else null
                 } catch (e: Exception) {
                     null
                 }
             }
-            if (mSalt == null) {
-                generateSalt(context)
-            }
+            if (mSalt == null) generateSalt(context)
         }
         return mSalt
     }