Error:Program type already present: android.arch.lifecycle.LiveData

Apparently, this is intended behavior:

com.firebaseui:firebase-ui-firestore:3.1.0 depends on android.arch.lifecycle:extensions:1.0.0-beta1. Switching to version 3.2.2 fixes the issue by using the Lifecycle 1.1 libraries that Support Library 27.1.0 are built upon. - Issue Tracker

For me, removing the firebase-ui dependencies solved the issue since I wasn't even using the library in the first place.

I had the very same problem today when I raised the support library version.

Try to replace all '27.1.0' with '27.0.2'

---

Later on I did manage to remove the error by upgrading other libraries as well. THis is my current working state: root gradle:

buildscript {
    ext.kotlin_version = '1.2.21'
    ext.support_version = '27.1.0'
    ext.anko_version = '0.10.4'
    ext.android_plugin_version = '3.0.1'
    ext.google_services_version = '11.8.0'

    repositories {
        google()
        jcenter()
        maven { url 'https://maven.fabric.io/public' }
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath "org.jetbrains.kotlin:kotlin-android-extensions:$kotlin_version"

        classpath 'com.android.tools.build:gradle:3.1.0-beta4'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
        classpath 'com.google.gms:google-services:3.1.1'
    }
}

allprojects {
    repositories {
        google()
        jcenter()
        maven { url "https://jitpack.io" }
    }
}

////////////////// app gradle libraries:

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation('com.crashlytics.sdk.android:crashlytics:2.9.1@aar') {
        transitive = true
    }

    // kotlin:
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
    implementation "org.jetbrains.anko:anko-common:$anko_version"
    implementation "org.jetbrains.anko:anko-commons:$anko_version"
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:0.22.3'

    // support libraries:
    implementation "com.android.support:recyclerview-v7:$support_version"
    implementation "com.android.support:support-v4:$support_version"
    implementation "com.android.support:design:$support_version"
    implementation "com.android.support:appcompat-v7:$support_version"
    implementation "com.android.support:cardview-v7:$support_version"
    implementation "com.android.support:support-vector-drawable:$support_version"

    // misc:
    implementation 'com.github.d-max:spots-dialog:0.7@aar'
    implementation 'com.squareup.picasso:picasso:2.5.2'
    implementation 'com.android.support.constraint:constraint-layout:1.1.0-beta5'
    implementation 'com.backendless:backendless:4.4.0'
    implementation 'io.nlopez.smartlocation:library:3.3.3'

    // Google services:
    implementation "com.google.firebase:firebase-core:$google_services_version"
    implementation "com.google.firebase:firebase-auth:$google_services_version"
    implementation 'com.firebaseui:firebase-ui-auth:3.2.2'

    implementation "com.google.android.gms:play-services-location:$google_services_version"
    implementation "com.google.android.gms:play-services-auth:$google_services_version"

    implementation('com.google.api-client:google-api-client:1.23.0') {
        exclude group: 'com.google.code.findbugs', module: 'jsr305'
    }
}

///////////////

I also upgraded graddle-wrapper.properties to:

#Wed Dec 20 15:08:34 CET 2017
distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip

This post is the top search result for the very similar error: "Program type already present: android.arch.lifecycle.ViewModelProvider$Factory"

My project uses Room and LiveData, but not firebase. The following changes removed the error:

FROM:

implementation 'android.arch.persistence.room:runtime:1.0.0'
annotationProcessor 'android.arch.persistence.room:compiler:1.0.0'
implementation 'android.arch.lifecycle:extensions:1.0.0'
annotationProcessor 'android.arch.lifecycle:compiler:1.0.0'

TO:

implementation 'android.arch.persistence.room:runtime:1.1.1'
annotationProcessor 'android.arch.persistence.room:compiler:1.1.1'
implementation 'android.arch.lifecycle:extensions:1.1.1'
annotationProcessor 'android.arch.lifecycle:compiler:1.1.1'

--- UPDATED ANSWER ---

My previous answer was aimed at solving this error. However, I thought it would be worth presenting it again using best practises:

App level build.gradle file:

// Room components
implementation "android.arch.persistence.room:runtime:$rootProject.roomVersion"
annotationProcessor "android.arch.persistence.room:compiler:$rootProject.roomVersion"
androidTestImplementation "android.arch.persistence.room:testing:$rootProject.roomVersion"

// Lifecycle components
implementation "android.arch.lifecycle:extensions:$rootProject.archLifecycleVersion"
annotationProcessor "android.arch.lifecycle:compiler:$rootProject.archLifecycleVersion"

Project level build.gradle file:

ext {
   roomVersion = '1.1.1'
   archLifecycleVersion = '1.1.1'
}

Reference:
https://codelabs.developers.google.com/codelabs/android-room-with-a-view/#2