Kotlin
Create an Android project
New Android Project
Create new a app-to-phone folder inside the vonage-tutorial folder:
mkdir app-to-phone
Open Android Studio and, from the menu, select File > New > New Project.... Select a Empty Activity template type and click Next.

Enter messaging as project name, point location to previously created vonage-tutorial/messaging folder, select as Kotlin language and press Finish button.
You now have a brand new Android Project.
Add Client SDK dependency
To add the Client SDK to the project, add the following dependency in the module-level build.gradle file.:

dependencies {
// ...
implementation 'com.vonage:client-sdk-chat:1.3.0'
}
Creating an Android chat app
Create a Android application that enables users to message each other using the Android Client SDK and Kotlin.
手順
1
Introduction to this task2
Prerequisites3
Create a Vonage Application4
Create a conversation5
Create the users6
Generate JWTs7
Create an Android project8
Building the log in interface9
ChatClient10
Building the chat interface11
Chat events12
Sending a message13
What's next?