# FlickerSpec: LED Flicker Test — Audit, Compliance & Eye Strain > Audit, Compliance & Eye Strain (iPhone/iPad app by Corey Thomas Slick.) - Source: https://appshunter.io/ios/app/flickerspec-led-flicker-test/id6759629660 (this page in markdown: same URL + `.md`) - Developer: [Corey Thomas Slick](https://appshunter.io/developer/1818871667) - Category: Utilities, Business - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 26.0 · 12 MB - Languages: American English - Released: 2026-04-03 - Data updated: 2026-08-03 - User reviews in markdown: https://appshunter.io/ios/app/flickerspec-led-flicker-test/id6759629660/reviews.md ## What is FlickerSpec? Your new LEDs shouldn't be giving you headaches. If they are, the lights are almost certainly flickering — faster than your eyes can consciously detect, but fast enough to trigger migraines, eye strain, and fatigue. FlickerSpec turns your iPhone into a flicker meter, using the 240fps camera to measure exactly what your eyes can't. For compliance documentation — clinical engineering, facility management, EU Ecodesign certification — FlickerSpec generates PDF reports with IEEE 1789 and IEC PstLM verdicts that satisfy accreditation surveyors and lighting auditors. WHAT YOU MEASURE Quick Measurement (Free, unlimited) Live 240fps capture with real-time results: • Dominant flicker frequency in Hz • Percent Flicker and Flicker Index per IEEE 1789-2015 • Signal-to-noise ratio and confidence rating • Live luminance waveform and FFT spectrum • No daily limit — measure as many fixtures as you like Compliance Verdicts (Pro) Turn raw numbers into a documented decision: • IEEE 1789-2015 PASS/FAIL verdict against the published low-risk practice • Custom pass/fail thresholds when your specification differs • The standard and threshold applied are recorded with every saved measurement IEC Certified Measurement (Pro) 3-minute tripod capture for compliance documentation: • Short-Term Flicker Severity (PstLM) per IEC TR 61547-1:2015 • EU Ecodesign 2019/2020 PASS/FAIL (threshold: PstLM ≤ 1.0) • 8× oversampled LM flickermeter validated against all 5 IEC Table A.1 test vectors • Suitable for clinical engineering and lighting audit documentation Measurement Logging & PDF Reports (Pro) Every audit, documented: • Save measurements with GPS location, fixture photo, and notes • Single-measurement and session-summary PDF reports • PstLM + EU Ecodesign section included when applicable • Calibration certificate reference on every report • CSV export for spreadsheet workflows Calibration System (Free) Verify accuracy before any audit: • Built-in calibration web app generates a known-frequency reference signal • Point your iPhone at any screen showing the calibration page • Timestamped calibration certificate attached to all subsequent reports MEASUREMENT BANDWIDTH 240fps camera capture (Nyquist: 120 Hz) measures mains-driven LED flicker reliably: • 60 Hz flicker (half-wave LED drivers, US) — full accuracy • 120 Hz flicker (full-wave rectified, US) — frequency reliable; use the 3-min IEC flow for stable depth measurements • Above 120 Hz PWM and kHz drivers — outside camera bandwidth NO SUBSCRIPTIONS $49.99 one-time purchase unlocks everything: IEEE 1789 verdicts, IEC Certified Measurement, unlimited logging, PDF reports, CSV export, calibration certificates, report header customization with your company name and logo. Free tier: unlimited Quick Measurements with the full live readout — frequency, percent flicker, flicker index, SNR and confidence — plus free calibration. Privacy Policy: https://flickerspec.slick-engineering.workers.dev/privacy Terms of Use: https://flickerspec.slick-engineering.workers.dev/terms ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | FlickerSpec Pro | $49.99 | one-time | ## Version history (last 5 releases) ### 1.4.0 — 2026-07-28 Privacy and accuracy fixes: • GPS coordinates in reports, exports and on screen are now rounded to roughly 11 m. Six-decimal coordinates resolved to a specific address, and CSV exports published the raw value. • Percent signs now print correctly throughout PDF reports. • Measurement uncertainty is shown at a sensible precision instead of rounding down to 0.0%. • Focus is now held steady for the duration of an IEC Certified Measurement, so autofocus can no longer drift during a 3-minute capture. ### 1.3.0 — 2026-07-19 This update sharpens measurement accuracy: • Corrected the IEEE 1789-2015 pass/fail threshold to match the standard's published Recommended Practice, so compliance verdicts are now accurate across the full frequency range. • More precise flicker-frequency detection, with rejection of slow ambient light drift. • Steadier frame-rate estimation for more consistent readings. • Honest, clearly-labeled measurement uncertainty in reports. Custom pass/fail thresholds you set in Settings are now applied to the on-screen verdict, saved measurements, and reports. ### 1.2.1 — 2026-06-02 FlickerSpec is now free to download. • Refreshed icon and in-app palette designed to be comfortable for flicker-sensitive users (migraine, photophobia, light sensitivity). • Softened all verdict and warning colors to a low-saturation amber/sage/brick palette — easier on the eyes during long audits. • Pro tier dropped from $149.99 to $49.99 one-time. Quick Measurement (live IEEE 1789 check) and IEC Certified Measurement (3-minute PstLM tripod capture) continue unchanged. ### 1.2.0 — 2026-04-24 IEC Certified Measurement (Pro): FlickerSpec now produces a Short-Term Flicker Severity (PstLM) value per IEC TR 61547-1:2015 — the metric cited by EU Ecodesign 2019/2020, ANSI C82.77-6-2023, and WELL Building Standard V2. Mount your iPhone on a tripod, aim at the fixture, run a 3-minute capture, and FlickerSpec returns a PstLM value with a clear PASS/FAIL against the PstLM ≤ 1.0 threshold. The PstLM result appears on the Log Measurement screen and in the single-measurement PDF report, alongside the existing IEEE 1789-2015 verdict. Quick Measurement (the live handheld IEEE 1789 flow) continues unchanged. Under the hood: 8× oversampled flickermeter at 1920 Hz, full 6-biquad LM weighting filter cascade, 60-second settling discard, IEC-smoothed percentile bank, validated against all 5 IEC TR 61547-1 Annex A Table A.1 test vectors within ±5%. ### 1.1.0 — 2026-04-13 - Free tier now includes 5 measurements per day with daily reset - All raw metrics (Percent Flicker, Flicker Index, frequency, SNR) visible on every measurement - IEEE 1789-2015 compliance verdict now a Pro feature - Updated user manual with Settings and Pro upgrade screenshots - Improved error handling for GPS, camera, and storage failures ## More apps by Corey Thomas Slick - [Research Radar: Auto Briefings](https://appshunter.io/ios/app/research-radar-auto-briefings/id6746874818) - [Thermlapse – Thermal Timelapse](https://appshunter.io/ios/app/thermlapse-thermal-timelapse/id6756284960) - [CarSense: AI Car Diagnostics](https://appshunter.io/ios/app/carsense-ai-car-diagnostics/id6760952816) All apps by Corey Thomas Slick: https://appshunter.io/developer/1818871667 ## Related topics [flicker test](https://appshunter.io/ios/topics/flicker-test) · [flicker and flame](https://appshunter.io/ios/topics/flicker-and-flame) --- *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 2026-08-03.*