Today, Microsoft announced that it's killing off Sway on iOS in favor of the web experience. The presentation service was first introduced in 2014, and has sort of struggled to find its place in the Office lineup. It was designed to be sort of like a modern PowerPoint, allowing users to create beautiful presentations that are interactive and for all different screen sizes.
But now, the company is consolidating Sway. In the announcement, Microsoft was very clear that Sway isn't going away as a service, and the Windows 10 app is here to stay as well. It's just the iOS app that's going away.
Sway for iOS will stop being available from the App Store beginning on October 19, so not only will you be unable to acquire it, but you won't be able to update it either. Beginning on December 17, the app will shut down, and users will be prompted to use Sway for the web upon launching the app.
And of course, between now and December, users of the app will continuously get notifications that Sway for iOS is shutting down. Remember, all of your Sways will remain where you left them, and you can continue to access the service via the web app.