# Audio analysis apps for iPhone

Built iPhone apps like an oscilloscope and spectrum analyzer, used by sound engineers and teachers.

| Tag | Value | Confidence |
|---|---|---|
| Category | Software and apps | 94% |
| Earns from | One-time sales | 94% |
| Startup cost (estimate) | $100 to $1k | 43% (low) |
| Time (estimate) | Hands-off | 94% |
| Where | Online | 97% |
| Coding | Needs coding | 99% |

Source: [Your best passive income? (2014)](https://news.ycombinator.com/item?id=7094903), Hacker News, eo34, 2014-01-21
Page: https://allsidehustleideas.com/ideas/audio-analysis-apps-for-iphone-742ed8

## 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.