Applications are just a bunch of functions that get things done: APIs wrap those functions in easy to use interfaces so you can work with them without being an expert.
Agora is not for static video or audio. The next YouTube, Netflix, or Spotify won’t be built on Agora. It’s for interactive, real-time video and audio, like one-to-many livestreams, audio chat rooms, or one-on-one use cases like telemedicine or tutoring.
Paid advertising can be a tricky monetization model for marketplaces. On one hand, it holds promise as a high margin revenue stream. However, it can also interfere with supply curation.