# Swift programming book and exercise platform

Teaches people the Swift language with a self-written book and an online coding exercise platform. Money comes from selling these products.

| Tag | Value | Confidence |
|---|---|---|
| Category | Digital products | 49% (low) |
| Earns from | One-time sales | 81% |
| Startup cost (estimate) | $1k to $10k | 52% (low) |
| Time (estimate) | Hands-off | 84% |
| Where | Online | 98% |
| Coding | Needs coding | 94% |

Source: [Ask HN: What are your passive income sources?](https://news.ycombinator.com/item?id=12799864), Hacker News, andrei512, 2016-10-26
Page: https://allsidehustleideas.com/ideas/swift-programming-book-and-exercise-platform-66c5c7

## About this data

- Sources are public, first-person accounts: interviews, podcasts and community threads.
- Cost, time and the other tags are machine estimates, each with a confidence score.
- Income figures are the owner's own claim. We don't verify them.
- Link the idea page and its source. Call income figures the owner's unverified claim, and cost and time estimates.