iOS app update notification

You can use Harpy : this module trigger a UIAlertView when a new version of your app is available on the App Store.

Harpy is now depricated.Siren was ported from Harpy, as Siren and Harpy are maintained by the same developer. As of December 2018, Harpy has been deprecated in favor of Siren.

1. Apple provides an existing API to get the latest app information from your app on the App Store:http://itunes.apple.com/jp/lookup/?id=app_id

Ex: http://itunes.apple.com/jp/lookup/?id=1005582646

Ex for a US app: http://itunes.apple.com/lookup/?id=myAppIDNumberFromTheAppStore

Note that this is separate from the App Store Connect API. If you use that, you'll need to generate a token before making the request. Please review the documentation on the API first or you will get a response with empty results.

https://developer.apple.com/documentation/appstoreconnectapihttps://developer.apple.com/documentation/appstoreconnectapi/generating_tokens_for_api_requests

The response of the iTunes API has a "version" field that is within the "results" field. It has the version number of the latest build on the App Store.

In AppDelegate->didFinishLaunchingWithOptions, you can call the above API.

2. The way to get current version on user's device:

Obj-C.

NSString *currentAppVersion = [[[NSBundle mainBundle]    infoDictionary] objectForKey:@"CFBundleShortVersionString"];

Swift (4.2)

var currentAppVersion = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String

Now you can compare the version number from 1 and 2 to show an alert or notification to the user when there is an updated app on the App Store.