# FreqCheck : See Sound — ISO 17025 Certified Analyzer > ISO 17025 certified frequency analyzer for iPhone/iPad, 1-100 Hz spectrum. (iPhone/iPad app by Abundance Sea, LLC.) - Source: https://appshunter.io/ios/app/freqcheck-see-sound/id6760624311 (this page in markdown: same URL + `.md`) - Developer: [Abundance Sea, LLC](https://appshunter.io/developer/1885377023) - Category: Utilities, Education - Price: Free with in-app purchases - Rating: 5.00/5 from 3 App Store ratings - Age rating: 12+ - Requires: iOS 18.6 · 16 MB - Languages: American English - Released: 2026-04-05 - Data updated: 2026-08-19 - Monetization: free with in-app purchases - User reviews in markdown: https://appshunter.io/ios/app/freqcheck-see-sound/id6760624311/reviews.md ## What is FreqCheck? Identify sources, audit content, or import lab audio files. FreqCheck is the first and only Class 1 Mobile Lab App — an ISO/IEC 17025-calibrated, NIST-traceable spectral engine powered by IND CORE™ (U.S. Patent No. 12,659,418) that adapts to your expertise. You've heard it. That low, persistent hum no one else seems to notice. That frequency track promising precise therapeutic tones that may or may not actually be there. That vibration in your chest you cannot explain. It doesn't matter what you were told — FreqCheck lets you measure it. TWO POWERFUL INSTRUMENTS. ONE SEAMLESS APP. FreqCheck houses two modes in a single app: a streamlined everyday scanner and a raw, unfiltered Pro Input Mode (PIM), backed by the same certified engine that makes this the first and only Class 1 Mobile Lab App on the market. The engine bridges to professional external DAQ hardware and USB interfaces via direct, DC-coupled line-in inputs, accepting calibrated telemetry with zero attenuation. That means no extra software suites in the field, and no wondering if your tool is capable. One app scales instantly from your iPhone's microphone for a quick check to raw lab capture from dedicated gear. Whatever the moment demands, you have it in your hand. PRO INPUT MODE (PIM): ENTERPRISE METROLOGY PIM grants direct manual control over critical hardware variables — sample rate locks, ADC voltage ceilings, sensor sensitivity coefficients — bypassing standard mobile audio filters and auto-gain compression entirely. Built-in dual preset slots allow you to save and instantly recall your most frequently used hardware configurations for fast switching in the field. That means your field readings hold up next to expensive lab bench equipment, down to the sub-Hz decimal. The numbers you capture are the numbers a lab would produce — no asterisks, no caveats. OFFLINE MEDIA AUDITING: The engine natively ingests raw video and lossless audio formats (.wav, .flac, .alac, .aiff, .m4a, .mp3), applying the same calibrated metrology math to pre-recorded files as it does live feeds. That means you can audit digital claims, verify therapeutic frequency tracks, and conduct forensic analysis — completely offline. The truth hidden inside a file is one import away. FORENSIC-GRADE PROOF. IN YOUR POCKET. Measurements are locked by a four-layer forensic security protocol: device-hash anchoring, real-time SHA-256 frame sealing, session hashing, and digitally signed PDF exports. Any attempt to alter telemetry breaks the seal and invalidates the document. What you present carries the same evidentiary weight as a controlled lab result. Certification #05122C9A 2602. ZERO-KNOWLEDGE PRIVACY FreqCheck runs on a strict zero-knowledge edge-computing framework — 100% of IND CORE™ processing happens locally on your device. No raw audio or video is ever uploaded or stored, and ad-tracking SDKs have been permanently removed. Every reading stays exactly where it belongs — with you. Starter: Free basic scans, ad-supported. Remove Ads: $2.99 one-time. *Pro Analyst Monthly: $19.99/month, 7-day free trial. *Pro Analyst Lifetime: $149.99 one-time. *Pro unlocks the LOGS vault, full ISO-compliant PDF Audit Reports, and the Nyquist Forum — a growing repository where field teams and investigators share certified, sealed telemetry data. THE MICROSCOPE MOMENT The microscope didn't create bacteria. It revealed what was always there. GPS didn't create your location. It made it knowable. FreqCheck makes the infrasonic spectrum visible, measurable, and provable — the first and only Class 1 Mobile Lab App, right in your hand. You don't need a degree. You need one tap. Privacy Policy: freqcheck.com/privacy.html Terms of Use: freqcheck.com/terms.html DISCLAIMER: Engineered metrology tool for research, acoustic consulting, and educational purposes only. Not intended for medical diagnosis. Full end-to-end NIST traceability requires an unbroken chain of calibrated external hardware. ## Key features - ISO 17025 certified frequency analysis - 1-100 Hz spectrum coverage - Live microphone input - Video audio extraction - Audio file analysis - Forensic-grade sealed reports - Single-tap activation ## Pricing and in-app purchases Base price: Free. **Subscriptions** | Subscription | Price | Period | | --- | --- | --- | | Pro Analyst | $19.99 | per month | **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Pro Analyst – Lifetime | $149.99 | one-time | | Remove Ads | $2.99 | one-time | ## Frequently asked questions about FreqCheck ### What is FreqCheck? FreqCheck is an ISO/IEC 17025:2017 certified frequency analyzer for iPhone and iPad. It measures sound frequencies in the 1 to 100 Hz spectrum, allowing users to see and analyze vibrations and tones. ### Does FreqCheck have ads? Yes, FreqCheck contains advertisements. As a free application with in-app purchase options, advertisements are displayed to support its continued development and availability. ### What are the different modes in FreqCheck? FreqCheck offers three input modes: LIVE for real-time microphone analysis, VIDEO to extract frequencies from video audio tracks, and AUDIO to audit the signal of any audio file. ### How does FreqCheck ensure the accuracy of its reports? Reports are sealed with forensic layers including Device-Hash Anchoring, SHA-256 Sealing, and are digitally signed PDFs. This ensures the data is locked to the device and any alteration invalidates the report. ### What is the price of FreqCheck? FreqCheck is available for free. There is an optional 'Pro Analyst' subscription available for $19.99 per month for users who require advanced features. ### What devices does FreqCheck support? FreqCheck is designed for iPhone and iPad devices. It supports external microphones and DC coupled line-in for enhanced audio input. ### How often is FreqCheck updated? The latest version, 1.1.1, was released on June 23, 2026. Updates are provided regularly to enhance functionality and reliability. ### What is the age rating for FreqCheck? FreqCheck has an age rating of 4+. This indicates it is suitable for users of all ages, with no mature content restrictions. ## Version history (last 5 releases) ### 2.0.2 — 2026-08-13 Version 2.0.2: Advanced PIM Workflow Control Built-in dual preset slot memory within Pro Input Mode (PIM) allows you to save custom configurations for your most frequently used measurement hardware and sensors. You can instantly recall saved sample rates, voltage ceilings, and sensitivity coefficients with a single tap instead of re-entering variables manually in the field. This completely eliminates setup friction, letting you deploy your lab configuration and capture certified data instantly. Streamlined workflows ensure maximum efficiency during every acoustic audit. ### 2.0.1 — 2026-08-09 Version 2.0.1: The Class 1 Mobile Lab App Upgrade This update includes performance improvements for Pro Input Mode (PIM), and stability enhancements to keep your live telemetry running smoothly. ### 2.0.0 — 2026-08-07 Version 2.0.0: The Class 1 Mobile Lab Upgrade FreqCheck 2.0.0 transforms your device from a diagnostic scanner into a dedicated, enterprise-grade metrology instrument. This architectural upgrade introduces true hardware bridging and laboratory-grade controls, establishing FreqCheck as the first and only Class 1 Mobile Lab App. PRO INPUT MODE (PIM) Raw Data Capture PIM bypasses standard mobile audio filters, automatic gain control, and heuristic smoothing entirely. Nothing touches your signal between the sensor and the engine. What reaches IND CORE™ is unadulterated, linear data — exactly what pure metrology demands. Direct Hardware Bridging Native support for professional external DAQ hardware and class-compliant USB interfaces via direct, DC-coupled line-in inputs. Zero attenuation means zero compromise. Your lab-grade sensors finally speak directly to your phone. Manual Calibration Overrides Enter your exact ADC voltage ceilings, sensor sensitivity coefficients, and hardware offsets by hand. This scales your mobile readings to match laboratory bench equipment precisely. Your field data and your bench data are now the same data — down to the sub-Hz decimal. Dynamic Sample Rate Locking Force the iOS audio session to handshake with external hardware at strict rates — 44.1 kHz, 48.0 kHz, 96.0 kHz , 192 kHz— while FFT bin resolution scales automatically to match your selected clock. Every calculation stays locked to true NIST-traceable precision. The math never drifts, no matter what hardware you connect. UNBREAKABLE AUDIT TRAILS Metrology Configuration Snapshot Your exact hardware parameters are now captured on a read-only dashboard block and permanently stamped onto every PDF export. Nothing about your setup is hidden or reconstructed after the fact. Your audit trail defends itself. Cryptographic Sealing Every PDF Audit Report is sealed with a unique SHA-256 hash anchored to your specific device and session telemetry. Tamper with the data, and the seal breaks instantly. Your reports now carry undeniable evidentiary weight. OFFLINE MEDIA ENGINE ALIGNMENT Symmetrical Processing The offline media engine has been rebuilt to mirror the live PIM pipeline exactly. Imported lossless audio and video files are now processed with full amplitude integrity and dynamic sample rate decoding. Whether you're capturing live or auditing a file, the math is identical — your forensic conclusions hold up either way. ### 1.1.4 — 2026-07-23 The Decentralized Laboratory FreqCheck has already established a new baseline for edge-computing metrology. With this update, we are completely liberating the acoustic laboratory. You no longer need to be tethered to cumbersome rack-mounted analyzers, tangled interfaces, or archaic desktop software to process high-resolution offline telemetry. These latest architectural upgrades reinforce the IND CORE™ as the undisputed standard for infrasonic analysis, making legacy workflows entirely obsolete. Professional File Ingestion: Process uncompressed and lossless .wav, .flac, .alac, .aiff, .m4a, and .mp3 files directly from your device or iCloud Drive. Extreme High-Fidelity Support: The engine now effortlessly handles massive audiophile files up to 24-bit / 384 kHz without processor bottlenecking or thermal throttling. Automated Standardization: All imported media is dynamically aligned to the 44.1 kHz laboratory standard prior to analysis. This ensures absolute mathematical consistency in FFT bin widths and sub-Hz measurements, completely eliminating the scaling drift commonly found in legacy software. Enterprise-Grade Metrology: Delivering the exact 32,768-point FFT mathematical rigor of traditional hardware, FreqCheck bypasses easily manipulated raw data outputs. Every live measurement and file import is instantly secured with an ISO 17025-aligned, SHA-256 cryptographically sealed PDF report. ### 1.1.3 — 2026-07-17 FreqCheck™ v1.1.3 Release Notes Standardized 48kHz Precision: Optimized the core processing engine to a native 48kHz standard, ensuring consistent, NIST-traceable results for all professional frequency audits. Enhanced Configuration Guidance: Added input requirements in Settings to ensure external hardware is locked to the 48kHz reference for professional-grade measurement accuracy. --- *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 2026-08-19.*