Progressive Web Apps

The Window Controls Overlay API allows installed PWAs to use some part of the window title bar for their own content [MDN, wicg/window-controls-overlay, alistapart.com, web.dev].

Web Capabilities (Project Fugu) is an effort to extend the web's capabilities to get closer to native apps [chromium.org, chrome-dev].

Progressive Web Apps may be published in the (mobile) app stores of several platforms (e.g. Android or iOS). A service than can help with the technical packaging of a PWA into an installable app is PWABuilder [pwabuilder.com, pwa-builder/pwabuilder].