Ionic 3 app taking huge time to run and build

200 pages is a lot…like REALL a lot. You basically have to compile each file in order to build the app. So your general options here are

1. Reduce the number of pages (make use of dynamic pages if you are using static content)
2. Update to the latest Ionic/Angular releases. The build tools on v3 have not been updated in some time because we want people to move off of v3. Upgrading to Angular 12 and Ionic 5 gives you not only a faster build process, but a much better developer experience.