Thumbmark Android

Thumbmark is the world's second best browser fingerprinting library. While not (yet?) as good, it's a free open source alternative to the market leading FingerprintJS. It is easy to use and easily extendable.

Thumbmark is open source (MIT).

🙏 Please don't do evil. Thumbmark is meant to be used for good. Use this to prevent scammers and spammers for example. If you see this library being used for evil, please raise an issue in this repo.

Installation

Jitpack

JitPack is an easy to use package repository for Git. It allows for publishing JVM and Android libraries. You'll need to add the following to your settings.gradle file in order to use JitPack dependencies:

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
        maven { url 'https://jitpack.io' }
    }
}

Once you have added JitPack to your project, you can import this library by adding the following to your apps build.gradle file:

dependencies {
    implementation 'com.github.thumbmarkjs:thumbmark-android:1.0.+'
}

Usage

The SDK provides a singleton by way of Thumbmark.kt This singleton provides two main values; A string identifier and a Fingerprint object.

Device identifier

Device identifiers are hashed, this means that they can not be converted back to a fingerprint. You can obtain a, SHA256 hashed, device identifier with the following:

import com.thumbmarkjs.thumbmark_android.Thumbmark

val id: String = Thumbmark.id(context = this)

If you have alternative hashing requirements, you can pass in your own hasher as follows (in the example below we're using SHA-1 however the function takes any String value consumable by MessageDigest):

import com.thumbmarkjs.thumbmark_android.Thumbmark

val id: String? = Thumbmark.id("SHA-1", this)

Device fingerprint

A device fingerprint is a strongly typed object, consisting of known hardware and software parameters/configurations/settings. You can obtain the device fingerprint as follows:

import com.thumbmarkjs.thumbmark_android.Thumbmark

val fingerprint: Fingerprint = Thumbmark.fingerprint(this)

Volatility

You can also set the desired level of volatility of the components that you'd like to base the computation of the device fingerprint on. Volatility, in the context of this library, is the concept of how likely a value is to change over time, or to put it alternatively, how "fragile" a value might be. You can configure the volatility of the component by calling setMaxVolatility before fetching the id:

import com.thumbmarkjs.thumbmark_android.Thumbmark

Thumbmark.setVolatility(ComponentVolatility.HIGH)
val id: String = Thumbmark.id(context = this)

Requirements

• Minimum SDK Version 21
• Compile SDK Version 34

Communication

• If you need help with a Thumbmark feature, open an issue here on GitHub and follow the guide. The more detail the better!
• If you'd like to discuss Thumbmark best practices, open an issue here on GitHub and follow the guide. The more detail the better!
• If you'd like to discuss a feature request, open an issue here on GitHub and follow the guide. The more detail the better!
• If you believe you've found a bug, open an issue here on GitHub and follow the guide. The more detail the better!
• If you want to contribute, submit a pull request!

Sponsors

ThumbmarkAndroid has been developed with 🧡 by Ordermentum. A huge thanks goes to them for donating their development efforts to bring ThumbmarkJS to the open source mobile community.

License

ThumbarkAndroid is released under the MIT license. See LICENSE for details.