# STEM Line Builder — AI-powered line design

> AI-powered line design (iPhone/iPad app by Ryo Ogasawara.)

- Source: https://appshunter.io/ios/app/stem-line-builder/id6793957353 (this page in markdown: same URL + `.md`)
- Developer: [Ryo Ogasawara](https://appshunter.io/developer/6793957355)
- Category: Sports, Health & Fitness
- Price: Free
- Age rating: 4+
- Requires: iOS 15.0 · 90 MB
- Languages: American English
- Released: 2026-08-14
- Data updated: 2026-09-07
- User reviews in markdown: https://appshunter.io/ios/app/stem-line-builder/id6793957353/reviews.md

## What is STEM Line Builder?

STEM Line Builder helps you design "lines" (routines) for longboard dancing.

Upload a carving video filmed head-on and the AI reads your posture to draw your board's trajectory as a top-down map. Then just tap a carve on the path and place a step you've learned -- only steps that fit the carves before and after are offered, so your line always flows.

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About subscriptions
- Yearly plan: 4,000 JPY / year (auto-renewing)
- Monthly plan: 500 JPY / month (auto-renewing)
- Lifetime: 8,000 JPY (one-time purchase, does not renew)

Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period, and are billed to your Apple ID. You can cancel anytime in your App Store account settings.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://ryoogasawara981.github.io/stem-line-designer/privacy.html


## Version history (last 4 releases)

### 1.1.5 — 2026-08-27

- Added Simplified Chinese language support
- Minor fixes and improvements

### 1.1.4 — 2026-08-26

- Rebuilt the in-app purchase system to fix an issue where Pro features weren't unlocking after purchase
- General stability improvements

### 1.1.1 — 2026-08-14

- Fixed an issue where My Steps showed all steps as mastered by default. New installs now start with no steps marked as mastered — tap each step's "Mastered" button to register it.
- Fixed an issue where "Auto-Generate" and other Pro features remained locked after purchasing the lifetime plan.

### 1.1.0 — 2026-08-13

No release notes.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-07.*