Google Play Services GCM 9.2.0 asks to "update" back to 9.0.0

The same situation was with the previous versions. It's annoing that new versions com.google.android.gms libraries are always releasing before plugin, and it's impossible to use new version because is incompatible with old plugin. I don't know if plugin is now required (google docs sucks). I remember times when it wasn't. The only way is wait for new plugin version, or you can try to remove plugin dependencies, but as I said I'am not sure if gcm will work without it. What I know the main feature of 9.2.0 version is new Awareness API https://inthecheesefactory.com/blog/google-awareness-api-in-action/en, if you didn't need it, you can use 9.0.0 version without any trouble.

Just put this line at the bottom of your app-module's (not project root's) gradle file.

apply plugin: 'com.google.gms.google-services'

Then rebuild your project.

I had the same problem, today 2016 - october - 06 I solved with this:

I changed all dependencies that began with 9.?.? to 9.6.1 I compiled with sdk version 24 and target version 17.

There is another packages in my solution because I used more things then only authentication.

After changed your build.gradle (Module:app) with the code below do it:

1. Put your package NAME in the line with the words applicationId "com.YOUR_PACKAGE_HERE"

2. Synchronize your project (Ctrl+alt+v) and Build Again.

This is the code of the file buid.gradle (Module:app) that worked for me:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 24
    buildToolsVersion "24.0.3"
    defaultConfig {
        applicationId "com.YOUR_PACKAGE_HERE"
        minSdkVersion 24
        targetSdkVersion 17
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })

    compile 'com.google.firebase:firebase-core:9.6.1'
    compile 'com.google.firebase:firebase-database:9.6.1'

    compile 'com.android.support:appcompat-v7:24.2.1'
    compile 'com.android.support:design:24.2.1'

    compile 'com.google.firebase:firebase-crash:9.6.1'
    testCompile 'junit:junit:4.12'

    compile 'com.google.firebase:firebase-messaging:9.6.1'

    compile 'com.google.firebase:firebase-ads:9.6.1'


    compile 'com.google.firebase:firebase-auth:9.6.1'


    compile 'com.google.android.gms:play-services:9.6.1'

}
apply plugin: 'com.google.gms.google-services'

Do you have the line

apply plugin: 'com.google.gms.google-services' 

line at the bottom of your app's build.gradle file?

I saw some errors when it was on the top and as it's written here, it should be at the bottom.