OpenTrace iOS App

OpenTrace is the open source reference implementation of BlueTrace.

BlueTrace is a privacy-preserving protocol for community-driven contact tracing across borders. It allows participating devices to log Bluetooth encounters with each other, in order to facilitate epidemiological contact tracing while protecting users’ personal data and privacy. Visit https://bluetrace.io to learn more.

The OpenTrace reference implementation comprises:

• Android app: opentrace-community/opentrace-android
• iOS app: opentrace-community/opentrace-ios
• Cloud functions: opentrace-community/opentrace-cloud-functions
• Calibration: opentrace-community/opentrace-calibration

Building the code

1. Install the latest Xcode developer tools from Apple
2. Install CocoaPods
3. Clone the repository
4. Run pod install at root of project

Configuration

Setting up Firebase for Staging and Production

The app relies on Firebase functions to work. More information can be obtained in the OpenTrace cloud functions repository.

1. After setting up Firebase, place your configuration files in the respective directories.

   |-- /FIREBASE
       |-- /PROD
           |-- GoogleService-Info.plist
       |-- /STG
           |-- GoogleService-Info.plist
   

2. In Targets > OpenTrace > Build Phases > Setup Firebase Environment GoogleService-Info.plist, you will find the code that is used to copy the Plist files into the Plist destination.

3. In Targets > OpenTrace > Info > URL Types, insert the GoogleService-Info.plist REVERSED_CLIENT_ID in URL schemes.

   

Configuring BlueTrace

You can find BlueTrace config variables at BluetraceConfig.swift.

Setting build variables

To configure STG and PROD variables, define them in Targets > OpenTrace > Build Settings > User-Defined and declare them in Info.plist.

These are some of the User-Defined variables.

PRODUCT_BUNDLE_IDENTIFIER
FIREBASE_STORAGE_URL
SERVICE_UUID
V2_CHARACTERISTIC_ID

Screenshot of User-Defined

Screenshot of Info.plist

Adding a privacy statement URL

Find ConsentViewController.swift and replace the placeholder with your privacy statement URL.

@IBAction func privacySafeguardsBtn(_ sender: Any) {
        // check if website exists
        guard let url = URL(string: "<PRIVACY_STATEMENT_URL>") else {
            return
        }
...

Setting Firebase remote config

The "Share" message uses Firebase remote config. The key is "ShareText". If it is unable to be retrieved, the app falls back to defaultShareText.

Debug Screen

There is a debug screen accessible within the staging version of the app. This allows you to view the app's Bluetooth communication log. To access it, you first have to set up the app. Then, tap on the home screen image.

Linting

There's a build script in Targets > OpenTrace > Build Phases > Swiftlint which runs SwiftLint on Build. Run {PODS_ROOT}/SwiftLint/swiftlint autocorrect to auto-fix some linting errors.

Security Enhancements

SSL pinning is not included as part of the repo

Statement from Apple

The following is a statement from Apple: "To ensure the credibility of health and safety information, Apple is only accepting COVID-19 related apps from recognised entities such as government organisations, health-focused NGOs, companies deeply credentialed in health issues, and medical or educational institutions. Only developers from one of these recognized entities should submit an app related to COVID-19 to the App Store.

For more information visit https://developer.apple.com/news/?id=03142020a"

Known issues

iOS has limitations on background Bluetooth activity. Details are documented in the white paper at https://bluetrace.io.