For an Android project, the new configurations came with the Android Gradle Plugin 3.0. So unless you are still using the 2.x version of Android Studio / Android Gradle plugin, the use of compile is deprecated. So you should use implementation, even for an app.

Configuration 'compile' is obsolete and has been replaced with 'implementation'.
It will be removed at the end of 2018




Configuration 'debugCompile' is obsolete and has been replaced with 'debugImplementation'.
It will be removed at the end of 2018




Configuration 'releaseCompile' is obsolete and has been replaced with 'releaseImplementation'.

It will be removed at the end of 2018

dependencies {

    compile 'com.android.support:recyclerview-v7:26.1.0'

    debugCompile 'com.squareup.leakcanary:leakcanary-android:1.5.4'
    releaseCompile 'com.squareup.leakcanary:leakcanary-android-no-op:1.5.4'

}

dependencies {

    implementation 'com.android.support:recyclerview-v7:26.1.0'

    debugImplementation 'com.squareup.leakcanary:leakcanary-android:1.5.4'
    releaseImplementation 'com.squareup.leakcanary:leakcanary-android-no-op:1.5.4'

}