Java . Firstly Java was the official language for Android App Development (but now it was replaced by Kotlin) and consequently, it is the most used language as well. Many of the apps in the Play Store are built with Java, and it is also the most supported language by Google.
Read moreWhat should I learn for Android backend?
7 Essential Skills You Need to be an Android Developer
Read moreIs there backend in Android?
A backend allows you to implement functionality such as backing up user data to the cloud, serving content to client apps, real-time interactions, sending push notifications through Google Cloud Messaging for Android (GCM), and more.
Read moreHow do I start learning backend?
How to become a Backend Developer?
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