How to detect first time app launch on an iPhone

📱How to Detect First Time App Launch on an iPhone 🚀

Are you an iOS app developer wondering how to detect the very first time an app is launched on an iPhone? Look no further! In this blog post, we will address this common issue and provide you with easy solutions to implement in your code. Let's get started! 🙌

The Problem 🤔

Consider the following scenario: you want to perform a specific action the first time your app is launched. You may be wondering how to detect this initial launch and execute the appropriate code.

Luckily, iOS provides a method called didFinishLaunchingWithOptions in the AppDelegate file that can help us achieve this. Within this method, we can add logic to differentiate between the first app launch and subsequent launches.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
  // if very first launch, perform actionA
  // else, perform actionB
}

But how exactly do we determine if it is the first launch? 🤷‍♀️

Solution 1: UserDefaults ✔️

One simple approach is to use the UserDefaults class, a mechanism for storing small amounts of data persistently across app launches. Here's how you can leverage it to detect the first app launch:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    
    if (![defaults boolForKey:@"HasLaunchedBefore"]) {
        // This is the first app launch
        [defaults setBool:YES forKey:@"HasLaunchedBefore"];
        [defaults synchronize];
        
        // Perform actionA for first launch
    } else {
        // Perform actionB for subsequent launches
    }
    
    // ... remaining code
}

In this solution, we retrieve the value of a boolean key called "HasLaunchedBefore" from UserDefaults. If the value is NO (indicating that the app has never launched before), we set it to YES and perform actionA. On subsequent launches, the boolean value is YES, and we perform actionB.

Solution 2: File System 📁

Another method to determine the first time app launch is by utilizing the file system. By checking for the existence of a file specifically created for first launch, we can detect if it's the app's initial run. Here's an example:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    NSString *filePath = [self filePathForFirstLaunch];
    
    if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
        // This is the first app launch
        [[NSFileManager defaultManager] createFileAtPath:filePath contents:nil attributes:nil];
        
        // Perform actionA for first launch
    } else {
        // Perform actionB for subsequent launches
    }
    
    // ... remaining code
}

In this solution, we use a method called filePathForFirstLaunch to generate the unique file path for the first launch file. If the file does not exist, indicating the initial app launch, we create it and then execute actionA. On subsequent launches, the file already exists, and we execute actionB.

Conclusion and Call-to-Action ✅

Now you know how to detect the first time an iOS app is launched on an iPhone! Whether you choose to use UserDefaults or the file system approach, both solutions will help you differentiate between the initial launch and subsequent launches. 🥳

Take your app development skills to the next level and start implementing these techniques in your projects today! If you have any further questions or other topics you'd like us to cover, feel free to leave a comment below. Happy coding! 💻📱

What's your go-to method for detecting an app's first launch? Let us know in the comments! 🗣️👇