Video summary

Amazfit Bip 6 Scientific Review (79$ Apple Watch Alternative?)

Main summary

Key takeaways

Product Review

Product reviewed

Amazfit Bip 6 (priced around $79) — positioned as a possible Apple Watch alternative, with testing focused on sports/health tracking.

Key features mentioned

  • Works with both Android and iOS
  • Large, vibrant display; generally praised for look and an “it just works” feel
  • Heart rate sensor reportedly similar to Amazfit’s T-Rex 3
  • Tracks:
    • Heart rate (compared to Polar H10 ECG chest strap)
    • Sleep stages (compared to Zmax EEG headband)
    • GPS (consistency test on repeated cycling routes)

What the reviewer liked (Pros)

Design & usability

  • Screen is big and vibrant
  • “Everything just works well”
  • Looks attractive; reviewer even suggests it may look better than Apple Watch

Indoor cycling heart-rate tracking

  • Excellent accuracy vs Polar H10
  • Dark gray “left wrist”: near-perfect match, correlation R = 1.00
  • Light gray “right wrist”: still very strong, R = 0.99
  • Individual sessions show almost perfect agreement, with only minor low/high outliers

Outdoor GPS tracking

  • Quick GPS signal acquisition (no long wait)
  • Decent track consistency across repeated rides
  • Overall described as “pretty decent” / “quite good”, especially for the price

Value

  • Reviewer calls it a good deal and “upper middle-class” for heart rate compared to older Amazfit performance at similar prices
  • For casual athletes, GPS should be “suffice”

Main issues (Cons / Limitations)

1) Outdoor cycling heart-rate tracking is inconsistent

  • Big discrepancy depending on wrist placement/unit
    • Left wrist (“Lefty”): R = 0.91
    • Right wrist (“Righty”): much worse, R = 0.71
  • Righty had many more points showing “too low” heart rate
  • Reviewer can’t fully explain the variation (possible sensor fit/physiology/unit defect), but warns that outdoor HR may be inconsistent
  • Recommendation for outdoor cycling HR: not as reliable as Apple Watch
    • Best alternatives listed: Pixel Watch 3 / Apple Watch / Garmin or Coros with chest strap

2) Running heart-rate tracking: unclear/inconclusive

  • Reviewer couldn’t run; results come from Raphael
  • First run: appears very accurate (lines overlap; strong agreement)
  • Second run (faster intervals): watch struggled in the middle, missing/under-capturing parts of HR
  • Verdict: limited data; inconclusive but not clearly great

3) Weightlifting / upper-body HR tracking is weak

  • Even though weightlifting is hard for watches, Bip 6 still shows limitations:
    • Left wrist correlation: R = 0.89
    • Right wrist correlation: R = 0.86
  • Pattern: higher HR during sets → watch more often shows low HR and misses peaks
  • Best-case note: leg day performed better (less tension on arm)
  • Conclusion: don’t use Bip 6 for weightlifting HR (especially upper body)
    • Alternatives suggested:
      • ECG chest strap (best if possible)
      • Apple Watch / PowerBeats Pro 2 earbuds with HR monitor
    • Apple Watch may also have dropouts if signal isn’t reliable

4) Sleep stage tracking is poor for REM

  • Compared vs EEG (Zmax headband) for 3 nights
  • Stage agreement:
    • Deep sleep: ~76%
    • Light sleep: ~76%
    • REM: only 29% agreement (major problem)
      • Much of REM was classified as light sleep (~68%)
  • Awake time agreement: ~37% (reviewer downplays awake due to reference limitations)
  • Sleep cycle reliability: reviewer suggests you shouldn’t trust detailed sleep cycles/stage analysis
    • Total “time in bed” may still be usable
  • Overall sleeping recommendation:
    • Use for basic sleep metrics (time in bed / rough depth impression)
    • Not recommended for sleep stages vs better options

GPS comparison / alternatives

  • Bip 6 GPS tested by repeatedly cycling the same route
    • Contrasted with devices that take longer to acquire GPS or perform worse mid-ride
  • Price performance:
    • Much better than Mi Band 9 Pro (per the reviewer’s recent review)
    • Still not as good as more expensive Garmin devices, but likely fine for casual users

Overall quantified highlights (as stated)

  • Indoor cycling heart rate correlation (vs Polar H10):
    • Left wrist: R = 1.00
    • Right wrist: R = 0.99
  • Outdoor cycling heart rate correlation:
    • Left wrist: R = 0.91
    • Right wrist: R = 0.71
  • Running (Raphael):
    • First run looked very accurate; second run had interval-related issues
    • (No explicit correlation score given)
  • Weightlifting heart rate correlation:
    • Left wrist R = 0.89
    • Right wrist R = 0.86
  • Sleep stage agreement (vs EEG):
    • Deep 76%, Light 76%, REM 29%
  • GPS performance:
    • “Quick acquisition” + “decent consistency” (no numeric score given)

Verdict / recommendation

  • Best for:
    • Indoor cycling heart-rate tracking
    • Basic sleep/time-in-bed
    • Solid GPS for the money
  • Not great for:
    • Outdoor cycling heart-rate reliability (especially depending on wrist/unit)
    • Weightlifting (upper body) heart-rate
    • Sleep stage/REM tracking

Concise recommendation: If you want a cheap smartwatch with excellent indoor HR and good GPS, the Amazfit Bip 6 is worth considering at ~$79. But if your priorities are outdoor cycling HR accuracy, weightlifting, or reliable sleep stage (especially REM), choose Apple Watch / Pixel Watch / chest-strap-based options.

Unique points mentioned (consolidated)

  1. $79 price; positioned as Apple Watch alternative for some
  2. Works on Android and iOS
  3. Attractive design and vibrant large display
  4. Testing method: 4 units tested systematically
  5. Indoor cycling HR accuracy: near-perfect correlations (1.00 and 0.99)
  6. Outdoor HR inconsistency by wrist placement: 0.91 (left) vs 0.71 (right), with frequent “too low” readings
  7. Outdoor HR comparison: not as good as Apple Watch; chest-strap devices recommended
  8. Running HR: first run good; second run less reliable during intervals (inconclusive)
  9. Weightlifting HR: 0.89 / 0.86, missing peaks; better on leg day than upper body
  10. Sleep stages: deep & light ~76%, REM 29%; don’t trust detailed cycles/REM
  11. Sleep total metrics (time in bed) likely OK
  12. GPS: quick lock, improved accuracy later in ride, good repeatability; better than some cheap alternatives
  13. Change narrative: Amazfit improved from previously weak HR to “upper middle-class” performance

Different speaker/subject perspectives

  • Rob (primary reviewer/scientist)

    • Provides structured testing and recommendations (indoor/outdoor cycling HR, sleep stages, GPS, and weightlifting behavior)
    • Highlights major outdoor HR inconsistency and strong indoor performance

  • Raphael (second test subject for some exercises)

    • Outdoor cycling HR: generally acceptable across sessions, but suggests positioning matters and indicates potential instability
    • Running: first run excellent; second run less reliable during intervals
    • Weightlifting: appeared slightly better than Rob’s results (peaks missed less severely, still not perfect)

Original video