At Daily, they offer a video call UI called Daily Prebuilt that can be easily integrated into any web application with just a couple of lines of code. They also introduced the ability to add live captions to their domains through their startTranscription() instance method in partnership with Deepgram. This feature allows users to transcribe audio from video calls, providing wider accessibility options and creating a great way to generate meeting notes. The tutorial focuses on pairing transcription with Daily Prebuilt and covers setting up with Daily and Deepgram, embedding Daily Prebuilt in a Next.js app, creating a transcription component, adding buttons to start and stop transcription methods, loading the live captions, optimizing the app for large amounts of text, downloading the transcript, and more. The tutorial also discusses how to optimize the app's performance by using react-window and react-virtualized-auto-sizer libraries to load only the most recent messages.