Just follow this path from top to bottom , to become an expert in android development

Complete map from Beginner to expert

Beginner

https://developers.google.com/android/for-all/vocab-words/?hl=en

https://www.udacity.com/course/ud837

https://www.udacity.com/course/ud836

https://www.udacity.com/course/ud839

https://www.udacity.com/course/ud843

https://www.udacity.com/course/ud845

https://www.udacity.com/course/how-to-use-git-and-github--ud775

https://in.udacity.com/course/firebase-in-a-weekend-by-google-android--ud0352

https://www.udacity.com/course/how-to-create-anything-in-android--ud802

Experienced

https://codelabs.developers.google.com/codelabs/build-your-first-android-app-kotlin/index.html

https://codelabs.developers.google.com/codelabs/build-your-first-android-app/index.html

https://codelabs.developers.google.com/?cat=Android

- Android Developers fundamentals

• https://www.gitbook.com/book/google-developer-training/android-developer-fundamentals-course-concepts/details

• https://www.gitbook.com/book/google-developer-training/android-developer-fundamentals-course-practicals/details

• https://www.youtube.com/playlist?list=PLlyCyjh2pUe9wv-hU4my-Nen_SvXIzxGB

• https://www.udacity.com/course/ud851

• https://in.udacity.com/course/writing-readmes--ud777

• https://in.udacity.com/course/google-location-services-on-android--ud876-1

• https://in.udacity.com/course/google-analytics-for-android--ud876-2

• https://in.udacity.com/course/monetize-your-android-app-with-ads--ud876-3

• https://in.udacity.com/course/add-google-maps-to-your-android-app--ud876-4

• https://www.udacity.com/course/ud855

Advanced Android development

• https://www.gitbook.com/book/google-developer-training/android-developer-advanced-course-concepts/details

• https://www.gitbook.com/book/google-developer-training/android-developer-advanced-course-practicals/details

Learn Design Skills

• https://www.udacity.com/course/ud862

• https://www.udacity.com/course/ud849

• https://in.udacity.com/course/mobile-design-and-usability-for-android--ud358

Testing android apps

• https://classroom.udacity.com/courses/ud855/lessons/f0084cc7-2cbc-4b8e-8644-375e8c927167/concepts/e4448227-af55-4883-ab88-e8ed717e2800

• https://developer.android.com/training/testing/fundamentals.html

• https://developer.android.com/training/testing/espresso/web.html

• https://developer.android.com/training/testing/espresso/lists.html

• https://developer.android.com/studio/test/espresso-test-recorder.html

• https://classroom.udacity.com/courses/ud855/lessons/f0084cc7-2cbc-4b8e-8644-375e8c927167/concepts/3183715d-7805-4a77-a817-5c2b52b8a7e8#

• https://junit.org/junit4/

• https://developer.android.com/topic/libraries/testing-support-library/index.html#Espresso

Example

• https://github.com/googlesamples/android-testing

• https://github.com/googlesamples/android-testing/blob/master/ui/espresso/IdlingResourceSample/app/src/androidTest/java/com/example/android/testing/espresso/IdlingResourceSample/ChangeTextBehaviorTest.java

• https://github.com/googlesamples/android-testing/blob/master/ui/espresso/IdlingResourceSample/app/src/main/java/com/example/android/testing/espresso/IdlingResourceSample/MessageDelayer.java

• https://developer.android.com/reference/android/support/test/espresso/IdlingRegistry.html

• https://classroom.udacity.com/courses/ud456

• https://in.udacity.com/course/associate-android-developer-fast-track--nd818/

Expert

https://in.udacity.com/course/android-performance--ud825

Firebase

• https://in.udacity.com/course/firebase-analytics-android--ud354

• https://firebase.google.com/docs/cloud-messaging/android/client

• https://firebase.google.com/docs/cloud-messaging/concept-options

• https://firebase.google.com/docs/cloud-messaging/android/device-group

• https://squawkerfcmserver.udacity.com/

• https://firebase.google.com/docs/cloud-messaging/server

• https://firebase.googleblog.com/2016/08/sending-notifications-between-android.html

https://www.npmjs.com/package/fcm-node

https://in.udacity.com/course/android-tv-and-google-cast-development--ud875B

https://in.udacity.com/course/android-auto-development--ud875C

https://in.udacity.com/course/gradle-for-android-and-java--ud867

https://in.udacity.com/course/shell-workshop--ud206

https://in.udacity.com/course/google-analytics-for-android--ud876-2/

https://in.udacity.com/course/technical-interview--ud513

https://in.udacity.com/course/monetize-your-android-app-with-ads--ud876-3/

https://in.udacity.com/course/kotlin-for-android-developers--ud888 Thank you , for this links.