What are small applications that can be accessed over the web

There are several ways of targeting mobile devices when making a web application:

Responsive web design can be used to make a web application - whether a conventional website or a single-page application viewable on small screens and work well with touchscreens.

Progressive Web Apps are web applications that load like regular web pages or websites but can offer the user functionality such as working offline, push notifications, and device hardware access traditionally available only to native mobile applications.

Native apps or "mobile apps" run directly on a mobile device, just as a conventional software application runs directly on a desktop computer, without a web browser (and potentially without the need for Internet connectivity); these are typically written in Java (for Android devices) or Objective-C or Swift (for iOS devices). Recently, frameworks like React Native, Flutter, Xamarin, and FuseTools allow the development of native apps for all platforms using languages other than each standard native language.

Hybrid apps embed a mobile web site inside a native app, possibly using a hybrid framework like Apache Cordova and Ionic or Appcelerator Titanium. This allows development using web technologies (and possibly directly copying code from an existing mobile web site) while also retaining certain advantages of native apps (e.g. direct access to device hardware, offline operation, app store visibility).

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