Mobilekit is a powerful mobile UI Kit template for any mobile websites and your pwa projects. Easy to use with components. Based on Bootstrap 5.
Mobilekit - PWA HTML Mobile UI Kit Template (bragherstudio.com)
Mobilekit - Bootstrap 5 Based HTML Template by Bragher | ThemeForest
Ionic is an open source UI toolkit for building performant, high-quality mobile and desktop apps using web technologies — HTML, CSS, and JavaScript — with integrations for popular frameworks like Angular, React, and Vue.
Open-Source UI Toolkit to Create Your Own Mobile or Desktop Apps (ionicframework.com)
Bitter is a powerful HTML mobile template for any project, easy to use. Based on Bootstrap 5.
Bitter comes with components and pages you may need.
https://themeforest.net/item/bitter-multipurpose-mobile-application-template/25262018