How do you organize information exchange between two different applications?

There are several approaches to exchanging information between two different iOS applications:

• URL Schemes (Custom URL Schemes): each app registers a unique scheme, and one app can open another by passing parameters through the URL.

• Universal Links: a more modern method that allows opening an app via a link if it is installed.

• UIPasteboard (Shared Clipboard): apps can exchange data through a shared clipboard.

• App Groups and Shared Container: if the apps belong to the same developer, a shared group can be configured to use a shared container for data storage.

• Keychain Sharing: for exchanging sensitive data between apps of the same developer.

Example of using Custom URL Scheme:

// In the first app
if let url = URL(string: "myapp2://data?value=123") {
    if UIApplication.shared.canOpenURL(url) {
        UIApplication.shared.open(url)
    }
}

// In the second app, handle the incoming URL in AppDelegate
func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
    if url.scheme == "myapp2" {
        // handle parameters
        return true
    }
    return false
}