Norwegian HIIT starting at 30 seconds, scaling to the full 4×4 protocol
Test first. Train right.
Stage
Not given
Not given
Founded
Not given
Not given
Based in
PL
Not given
Pricing model
Free
Freemium
Pricing
Not given
Free testing and one free Coach report. Coach subscription: US$3.99 per month or US$19.99 per year (prices shown in local currency on App Store). New subscribers get first 3 months free for a limited time.
Key features
Progressive on-ramp starting at 30-second intervals
Voice-guided coaching throughout entire session
Lock Screen and Dynamic Island display (iOS 17+)
Works with screen locked and music playing
Available in four languages
Personalized heart-rate zones computed from max heart rate
Native Apple Watch Workout app integration
Adaptive level progression based on recovery data
No account, no ads, no tracking
Test 10 fitness dimensions and 68 metrics in 15 minutes using camera and phone sensors
AI-powered Body Score from 0-100 normalized against age- and sex-matched norms
Identify your #1 limiting fitness dimension
AI Coach generates periodized four-week training plans targeting your weakest area
Camera-based jump height measurement up to 240 fps with manual frame adjustment
Bar speed (VBT) tracking for squat, bench, deadlift, overhead press and row
Unlimited Coach reports and meal and posture analysis with subscription
Data stays on your phone; AI processing requests sent to third-party provider only on demand
Optional iCloud backup of test history under your control
What makes it different
Structured progressive on-ramp that no other 4×4 resource offers
Never forced progression: holds levels based on recovery data and never uses shame mechanics
Privacy by design with no account or tracking required
Works completely with screen locked and music playing through voice cues
No account or login required; testing is completely free with no card needed
Measures 68 metrics across 10 dimensions using phone camera for most tests, requiring no equipment for baseline assessment
Scores all results on same 0-100 scale against age- and sex-matched population norms for direct comparison
AI Coach pinpoints your single weakest fitness dimension and builds targeted training plans to fix it
iPhone-only with pose estimation powered by Apple's on-device technology and Health app integration
Crescendo 4×4
BodyBench