I am working on a project of iOS app which is used by front-line employees when they provide service to customers. This app needs good user eductation, so we don't need to provide training to the employees. It also needs good user experience and user interface design, since both employees and customers will see the interface. But now we are not satisfied with UI/UX. We want to refer to some apps with good UI/UX. Everyone in the team has to introduce some apps, but I haven't used many apps. Can you recommend me several iOS/Android Apps with good user experience and user interface design? So I can use and learn from them.