Someone who can make a boxy UI, hook those boxes up to {{text templates}}, and make GET/POST/PUT/DELETE calls (to RESTful API just thinly wrapping a SQL DB) can recreate a shocking number of popular web and mobile apps. Those are CRUD apps.
Non-CRUD apps have an unusual (non-boxy) UI, non-trivial backend processing/integrations, or both.
Someone who can make a boxy UI, hook those boxes up to {{text templates}}, and make GET/POST/PUT/DELETE calls (to RESTful API just thinly wrapping a SQL DB) can recreate a shocking number of popular web and mobile apps. Those are CRUD apps.
Non-CRUD apps have an unusual (non-boxy) UI, non-trivial backend processing/integrations, or both.