CDN versus Application-Level Caching: When Should You Use Each?

hey everyone im tryna get a clearer pic of where to best implement caching in our stack. were setting up some new services and thinking bout how to speed things up. weve got a cdn in place for static assets, but im wondering bout caching dynamic api responses. is it generally better to cache these at the cdn level if possible, or should we be implementing caching directly within our app servers (like redis, memcached) tho whats better depends. what makes you decide where to put it. are there specific types of data or response patterns that lean towards one approach over the other. curious to hear your thoughts and experiences