This video features a competitive coding challenge between Riley Brown, a self-proclaimed “Vibe Coder,” and Vishall Dwey, a Senior iOS Developer with 10 years of experience. The goal is to build a clone of “Granola,” a $250 million AI note-taking app, using only AI tools and a strict limit of five prompts each. The rules prohibit manual code editing, forcing the participants to rely entirely on their prompt engineering skills and chosen AI frameworks.

The Challenge and Requirements

The participants are tasked with creating a functional iOS app that includes specific features: voice recording, audio transcription, AI-generated summaries, calendar synchronization, and folder organization. The challenge utilizes a “snake style” turn-based format for the ten total prompts.

• Riley (Vibe Coder): Uses Vibe Code, a tool optimized for mobile app generation.
• Vishall (Senior Dev): Uses Claude Code directly in the terminal combined with Xcode.

Key Development Highlights

Vishall’s Approach: Vishall starts by setting up the project architecture in Xcode via Claude Code. He initially relies on Apple’s native frameworks (Event Kit for calendars and Apple Speech for transcription). His process is plagued by build errors, requiring him to use valuable prompts to fix bugs and clear cached data. While he successfully integrates calendar views and a custom waveform animation, he struggles with implementing the folder logic and integrating OpenAI’s Whisper API smoothly.

Riley’s Approach: Riley strategically omits the calendar integration in his first prompt to focus on core functionality (recording and folders). This approach results in a smoother initial build. He later integrates the calendar and switches to OpenAI’s Whisper model for better transcription. Riley’s workflow encounters fewer fatal errors, allowing him to focus his final prompts on UI polish and fixing specific rendering bugs.

The Final Verdict

After five prompts each, the two apps are compared:

• Vishall’s App (“Cereal”): Features a robust “Today” calendar view and a visually appealing recording animation. However, the folder functionality is buggy, failing to save meetings into specific categories, and the UI lacks consistency.
• Riley’s App (“Oatmeal”): Delivers a more polished user experience with a clean design. Crucially, the folder organization works correctly, allowing for multiple recordings within events. The app successfully handles calendar syncing and provides clear transcriptions and summaries.

Ultimately, Riley’s “Vibe Coding” approach produced a more functional and polished prototype within the constraints, though Vishall’s app demonstrated potential with more complex native integrations.

Mentoring question

How does the strategic decision to delay complex integrations (like the calendar feature) impacting the overall stability and velocity of the development process compared to attempting a full-stack implementation in the first prompt?

Source: https://youtube.com/watch?v=NnYLzGMk8Tg&is=Q9ab4UDrYaXjfK5W