.app

.app is a generic top-level domain designed for apps and the businesses, products and developers behind them. IANA records show that the extension was added to the DNS root in 2015, with Charleston Road Registry Inc. as the sponsoring organization. Google Registry later opened .app for general registration in May 2018.

The meaning of the extension is unusually clear. A name ending in .app immediately suggests software or an application, which can make it useful for mobile apps, web apps, SaaS products, developer tools, games and other software-based services. It can also provide a dedicated web address for an app whose main distribution happens through an app store, giving the developer a place for documentation, download links, release information, support or other product content.

One of the most important differences between .app and many other domain extensions is its HTTPS requirement. The entire .app top-level domain is included in the HSTS preload list. Modern browsers therefore expect .app websites to use encrypted HTTPS connections, and a website that is not configured for HTTPS will not load normally. Anyone planning to use a .app domain should make sure that the hosting setup supports HTTPS and that a valid TLS certificate is configured before launching the site.

This HTTPS requirement improves connection security, but it should not be confused with a guarantee that every website or application using .app is trustworthy. Visitors should still evaluate the organization, software and content behind a domain in the same way they would with other extensions.

.app is an open namespace. Since general availability began, anyone can register an available .app name through a participating registrar, subject to registry and ICANN policies. Individual names may already be registered, reserved or classified as premium, and trademark or other legal rights can still affect whether a particular name is appropriate to use.

The strong meaning of .app is both an advantage and a limitation. It is highly descriptive when an application is the central product, but it may be less suitable for a company that expects its identity to expand well beyond software or apps. In that situation, a broader domain extension may provide more flexibility over the long term.