I want to use **firebase UI** in my android app, but it constantly give build error while adding dependency in `android studio
i tried the tutorial at <https://github.com/firebase/FirebaseUI-Android#using-the-library-in-your-android-app> and
<https://www.firebase.com/blog/2015-08-27-firebaseui-makes-mobile-easy.html>
But both gives me same error

here is my build.gradle file

```
apply plugin: 'com.android.application'

android {
  compileSdkVersion 21
  buildToolsVersion '21.1.2'

  defaultConfig {
    applicationId "re.book.bookify"
    minSdkVersion 15
    targetSdkVersion 21
    versionCode 1
    versionName "1.0"
  }

  packagingOptions {
    exclude 'META-INF/LICENSE'
    exclude 'META-INF/LICENSE-FIREBASE.txt'
    exclude 'META-INF/NOTICE'
  }

  buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
  }
}

dependencies {
  compile fileTree(dir: 'libs', include: ['*.jar'])
  compile 'com.android.support:appcompat-v7:22.2.0'
  compile 'com.google.android.gms:play-services:7.5.0'
  compile 'com.github.shell-software:fab:1.1.2'
  compile 'com.github.shell-software:viewmover:1.1.0'
  compile 'com.github.shell-software:uitools:1.1.0'
  compile 'com.firebase:firebase-client-android:2.3.1+'
  compile 'com.firebase:firebase-ui:0.2.0'
}

```