thirdweb Android SDK

Simple smart wallet connection for Android apps

Features

• Let user connect to their smart wallet with a single line of code
• Automatic session keys to grant your app scoped access to user's wallet
• Best used in conjunction with thirdweb engine as the transaction executor
• Standard OAuth2 flow with access and refresh tokens which can be used for your own server's authentication
• Supports any EVM chain

Installation

Add the following to your build.gradle file:

dependencies {
    implementation 'com.thirdweb:connect:<latest_version_here>'
}

You can view the latest published version on maven central.

Usage

Initialize the SDK

If you haven't already, create a project and obtain a free client id from the thirdweb dashboard.

Create a new instance of the SDK with your clientId and redirect url. You should only keep one instance of the SDK in your app:

import com.thirdweb.Thirdweb

const val clientId = "your_client_id" // get this from the thirdweb dashboard
const val redirectUrl = "your_app://callback" // this should be a deeplink scheme that your app can handle

val thirdweb = Thirdweb(clientId, redirectUrl)

The redirectUrl is a deeplink scheme that should be registered in your AndroidManifest.xml file:

<activity android:name=".MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />
        <data android:scheme="your_app" android:host="callback" />
    </intent-filter>
</activity>

Login flow

To connect to the user's wallet, call the login method from your UI:

thirdweb.login(context)

This will open the authentication flow in a custom chrome tab.

Upon completion, your redirectUrl will be called with the auth result.

You can handle the result in your onCreate and/or onNewIntent method depending on your launchMode behavior:

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    // your code ...
    handleLoginCallback(intent)
}

override fun onNewIntent(intent: Intent?) {
    super.onNewIntent(intent)
    handleLoginCallback(intent)
}

private fun handleLoginCallback(intent: Intent?) {
    // will only trigger if the activity was started with the correct intent
    // you can also check if the intent has the correct action and data by calling thirdweb.isLoginCallbackIntent(intent)
    thirdweb.handleLoginCallback(baseContext, intent,
        // onSuccess callback, returns the user object, and auth token data usable as your own server auth
        onSuccess = { user, authToken ->
            Toast.makeText(
                this@MainActivity,
                "Logged in as: ${user.userAddress}",
                Toast.LENGTH_LONG
            ).show()
            showUI(user) // your app logic
        },
        // onError callback
        onError = { exception ->
            Toast.makeText(
                this@MainActivity,
                "Error: ${ex.message}",
                Toast.LENGTH_LONG
            ).show()
        }
    )
}

Once this process is done, you can now execute transactions on behalf of the connected users as long as they're within the scoped permissions.

We recommend using thirdweb engine, using a backend wallet as the session key address. This lets you execute any onchain transaction with a simple and performant REST API.

Get the user's wallet address

You can get the user's wallet address at any time by calling:

val user = thirdweb.getUser()
println(user.userAddress)

Get the user's auth token

You can get the stored auth token by calling:

val authToken = thirdweb.getAuthToken()
println(authToken.accessToken)

This is useful to authenticate your own server's API requests. The accessToken follows the JWT standard, and can be verified on your backend with a standard JWKS endpoint located at https://login.thirdweb.com/api/jwks.

This is a well known standard and has many third party libraries that can help you verify the token, like jose in NodeJS, or PyJWT in Python.

With this you have your whole authentication flow covered, including the user's wallet connection and your own server's API requests.

Logout

To disconnect the user's wallet, call:

thirdweb.logout()