Demon Plank - A Plank Timer That Stops When You Move

If you move, time stops.

Oni Plank is a plank-exclusive timer that monitors your joints in real-time using your smartphone's camera. The timer advances only while you remain still, and stops instantly if your body moves even slightly. Whether your arms drop or your hips sway, the demon never misses a thing.

Key Features

• AI-powered stillness detection — On-device pose estimation tracks 7 joint points including head, shoulders, elbows, and wrists. Joints that move are displayed in red, and the timer automatically stops/resumes.
• Identify what moved — The screen displays which joints collapsed, such as "(left shoulder, right elbow)"
• Fine-tune judgment strictness — Adjust severity (levels 1–10), response time (0.2–2.0 seconds), countdown (3–30 seconds), and toggle lower body detection on/off
• Distance guide — Real-time guidance on whether your entire body fits in the frame. Tells you if you're "too close" or "too far"
• Records are saved — Track total attempts, total time, and personal best, plus review history of seconds per attempt and stop counts. Complete a plank without stopping once and earn a "No-Stop Achievement!"
• Japanese and English support

Perfect for:

• People whose self-reported plank times tend to be vague
• People who count time even when their form breaks down
• People who want an "uncheateable referee" for home workouts

Privacy: Video never leaves your device

All pose estimation is processed entirely on your device. Camera footage, still images, and videos are never saved (not even temporary files). Analysis results such as joint coordinates are not sent externally, and history is stored only on your device.

Premium (Optional)

Ad-free / timer limit removal (free version: 60 seconds → up to 999 seconds). ¥300/month or ¥3,000/year.

System Requirements

Android 8.0 (API 26) or later / iOS 15.6 or later (iPhone and iPad compatible).

※This app is not intended for medical purposes, health diagnosis, or treatment. If you have any health concerns, please consult a doctor before use.

開発元サイト: FreeAppsStudio