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Helios decentralized Rewarding and Rating Model

The main function of the decentralized reward system is to incentivize Helios users in the use of the platform. Users will be able to collect this incentive, in the form of a fungible token, and will be able to spend it for benefits within the platform (access to premium features, access to premium content, access to external services).

Why a decentralized (blockchain-based) reward system?

  • An incentive system that is not dependent on a central issuer and has rules agreed by participants
  • A censorship-free and transparent incentive system

The following figure shows the general scheme of the rewarding system:

  • A user of the Helios network performs an action on the network that may be a candidate to be rewardable (according to system rules)
  • The rewarding module manages the associated rules and incentives, confirms the rewardable action and applies the transfer of the corresponding tokens to the user's wallet
  • The reward wallet accumulates such tokens as a balance of points that the user can use for other uses as if it were an internal currency of the system

Diagram - general scheme

As users contribute with valuable content or performing some of the identified rewardable actions on the network, they will earn Helios tokens rewards that will be directly linked to their relevance as a contributor on the Helios network. All rewards will initially transact via the Quorum Network through smart contracts.

A predetermined number of Helios tokens, based on the total daily activity directly linked with rewarding actions, will be issued at the end of each day as a Daily Reward Pool. An individual’s daily contribution will be determined by how much they contributed to the network that day relative to the entire community. This percentage will then be applied to the Daily Reward Pool to determine everyone’s daily token grants.

The following table outlines the scoring weight applied to each rewardable action to determine user contribution and relevance to the network:

Table - Scores

Hereafter, we present the main factors defined for the rewarding algorithms:

Table - Algorithm factors

The total contribution of a user in the Helios network for a Reward Period (initially set to 1 day) is the following:

Formula - Total contribution

The Relevance of this user is related to the whole contribution performed by the rest of the users in the network for a Reward Period:

Formula - Relevance

The number of tokens available for distribution to contributors in each Rewarding Period (reward mining) is based on a pre-set calculation but it also depends on the number of active users contributing to the network:

Formula - Total amount Formula - Total amount

Finally, the amount of Helios tokens that are transferred to each user’s wallet depend on the token production (reward mining) generated every Rewarding Period by Helios in the following way:

Formula - HLO

Utility of the Helios Token

Helios users will collect Helios rewarding tokens through the performance of activities and actions that are tagged as rewardable. These tokens will be collected in their mobile applications within a wallet module that will store the balance of tokens and the capability to transfer a partial or total amount in exchange of benefits accessible to each use case. We describe initial token utilities that will be defined within the scope of the different contexts and use cases where this token may be spent:

  • Access to premium content
  • Access to external services as a discount on the final price
  • Content promotion
  • Promotional campaigns for external services
  • Platform development governance (voting on new features and product roadmap)

For more information you can download D4.4 Rewarding Strategies.

Wallet for HLO

There is a decentralized application of Helios in the Bloomen wallet:

QR - Helios dApp

Project structure

This project has two main components:

  • An android SDK
  • A sample Android app

The android SDK is oriented to help integrating the Reward Module to an existing Android app. The sample app helps to see a way to use the SDK on a Kotlin based app.

Android SDK

There is a main class called RewardingSdk that have all the methods needed to use the Rewarding Module API. There are also some callbacks that needs to be implemented in order to use those methods. You can download the library file aar from the releases page:

Sample Android app

This is a simple kotlin app that shows a way to use the SDK. It is made up of activities and presenters. You can download de application file apk from the releases page:

Library usage


  • The app must be able to provide a user identifier and a context or use case identifier.
  • The minimum android version is 9 (Pie)
  • The app must grant the android.permission.INTERNET permission.


To use the Rewarding SDK, you need to copy the aar file into your app's library directory. Then, you need to add the following dependency to your app's gradle build file:

dependencies {
    implementation(name: 'helios-rewarding-sdk-debug', ext: 'aar')

Also, the app needs to apply some extra dependencies the SDK needs:

apply from: 'helios_rewarding_sdk.gradle'

This helios_rewarding_sdk.gradle is a file that needs to be placed into your app's gradle files. The file contains the following code:

dependencies {
    def ktor_version = '1.3.1'
    def multiplatform_settings_version = "0.5"
    implementation "com.russhwolf:multiplatform-settings:$multiplatform_settings_version"
    implementation "io.ktor:ktor-client-android:$ktor_version"
    implementation "io.ktor:ktor-client-gson:$ktor_version"
    implementation "io.ktor:ktor-client-auth-jvm:$ktor_version"
    implementation "io.ktor:ktor-client-logging-jvm:$ktor_version"


The Rewarding SDK has seven methods to interact with:

interface RewardingSdk {
    fun registerUser(userID: String, heliosContext: String, callback: RegisterUserCallback)
    fun getToken(callback: GetTokenCallback)
    fun removeToken(callback: RemoveTokenCallback)
    fun recordRewardableActivity(rewardableActivities: List<RewardableActivity>, callback: RecordRewardableActivityCallback)
    fun cancel()
  • The registerUser method is the one that calls the /auth/networkUser/register Rewarding Module API method. It registers a user to the Rewarding Module using an identifyer an some context/use case identifyer. The response of the API method is an access token that the Rewarding SDK stores into the Sharedpreferences settings.
  • The getToken method reads the access token stored into the Sharedpreferences, if any.
  • The removeToken method removes the access token stored into the Sharedpreferences, if any.
  • The recordRewardableActivity method calls the /activities/record API method. It registers the activity of the user accepting a list of RewardableActivity objects.
  • The cancel method allows the app to stop any other running SDK process.

Each one of this methods receive a callback object that needs to be implemented in order to manage the server response. Each callback is called by the onSuccess method when everything is OK and by the onError method when something go wrong.

interface RegisterUserCallback {
    fun onError()
    fun onSuccess()

The registerUser does not return any data, because it stores the access token automatically.

interface GetTokenCallback {
    fun onError()
    fun onSuccess(token: String)

The getToken returns the access token as a String.

interface RemoveTokenCallback {
    fun onError()
    fun onSuccess()

The removeToken does not return any data.

interface RecordRewardableActivityCallback {
    fun onError()
    fun onSuccess()

The recordRewardableActivitydoes not return any data.


Register user

SDK method
API method
SDK callback

This method registers a user to the Rewarding Module using an identifyer an some context/use case identifyer. The response of the API method is an access token that the Rewarding SDK stores into the Sharedpreferences settings.

Example of use

    fun registerUser(userID: String, context: String) {
        rewardingSdk.registerUser(userID, context, object: RegisterUserCallback {
            override fun onError() {

            override fun onSuccess() {

Record activity

SDK method
API method
SDK callback

This method registers the activity of the user accepting a list of RewardableActivity objects.

Example of use

    fun registerActivity(actions: List<Action>, date: String) {
        val rewardableActivities: MutableList<RewardableActivity> = mutableListOf()
        for (action in actions) {
            rewardableActivities.add(RewardableActivity(action = action.value, date = date))
        rewardingSdk.recordRewardableActivity(rewardableActivities, object: RecordRewardableActivityCallback {
            override fun onError() {
            override fun onSuccess() {

The List<Action> named actions is a collection of enumerable values of the enum Action. The RewardableActivity has two attributes: action and date. So you need to send to the API a list of predefined actions, each one with a date related to it.
The list of available actions:

enum class Action(val value: String) {

To develop


  • Install Android Studio GitHub


  • Open or import the existing project with Android Studio.
  • Write your code in Kotlin.
  • To generate a new aar file of the SDK, select the Build option in the Menu Bar, then select ReBuild project or click the Make Project icon.

License: Apache License 2.0