Jet Admin - Build business apps really fast
WebShell - Bundle web app to OS X app without coding
Retool - Build custom internal tools in minutes.
Ionic Portals - Portals is a supercharged iOS and Android Web View component for adding web-based experiences to native mobile apps.
Avo - Prevent human errors when implementing analytics
webtoapp.design - https://webtoapp.design turns websites into apps automatically. The apps work without an internet connection, show changes to your website whenever you change it and they follow design guidelines for apps, so they get accepted into the app stores.