How to link to TestFlight App in iOS

There are two things you need to do. First, check to see if TestFlight is installed. Then create a new link to your app.

NSURL *customAppURL = [NSURL URLWithString:@"itms-beta://"];
if ([[UIApplication sharedApplication] canOpenURL:customAppURL]) {

    // TestFlight is installed

    // Special link that includes the app's Apple ID
    customAppURL = [NSURL URLWithString:@"https://beta.itunes.apple.com/v1/app/978489855"]; 
    [[UIApplication sharedApplication] openURL:customAppURL];
}

This special https://beta.itunes.apple.com URL will be opened directly in TestFlight.

Finally, if you are using iOS 9 (or later), you need to make an addition to your Info.plist to get the canOpenURL: method to work.

If your app is linked on or after iOS 9.0, you must declare the URL schemes you want to pass to this method. Do this by using the LSApplicationQueriesSchemes array in your Xcode project’s Info.plist file. For each URL scheme you want your app to use with this method, add it as a string in this array.

[key]LSApplicationQueriesSchemes[/key]
[array]
    [string]itms-beta[/string]
[/array]

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