I've been integrating a cross‑platform file synchronization feature for our app, targeting Windows, macOS, iOS, Android, and Linux. While the core logic works, I keep hitting platform‑specific roadblocks. Below are the major challenges I've faced and the solutions that worked for me.

1. File System Differences

Permissions, case‑sensitivity, and reserved names vary across OSes.

// Example: Normalizing file paths
function normalizePath(path) {
    return path.replace(/\\/g, '/').toLowerCase();
}

2. Background Sync Limitations

Mobile OSes restrict background execution.

// iOS: Using BackgroundTasks
import BackgroundTasks

func scheduleSync() {
    let request = BGAppRefreshTaskRequest(identifier: "com.synchub.sync")
    request.earliestBeginDate = Date(timeIntervalSinceNow: 15 * 60)
    try? BGTaskScheduler.shared.submit(request)
}

3. Conflict Resolution

Implementing a deterministic merge strategy is key.

function resolveConflict(local, remote) {
    if (local.lastModified > remote.lastModified) return local;
    return remote;
}

Any other developers facing similar issues? Happy to discuss further or review code snippets.