--- schema_type: "SoftwareApplication" entity_type: "Mobile Application" app_name: "Frequency Counter+ Hz FFT" developer_entity: "Kyu-Hee Jang" bundle_id: "com.simonj.frequencycounter" app_store_id: "6761234058" category: "Utilities" primary_platform: "ios" primary_monetization: "Free" offline_capable: false market_region: "US" platforms: "iOS & Android" app_last_updated: "2026-08-17" report_date: "2026-08-20" last_verified: "2026-08-20T00:00:00.000Z" report_version: "1.0.42" total_reviews: 60 overall_rating: 2.5 sentiment: "Frustrated" sentiment_score: 25 confidence: "medium" confidence_score: 0.5 top_praise_theme: "The core functionality provides a useful tool for measuring hair clipper revolutions per minute" top_complaint_theme: "Full screen advertisements and fake security warnings disrupt the user experience and create distrust" review_sample_size: 8 total_review_count: 8 analyzed_review_count: 8 data_age_days: 41 momentum_velocity: "active" intelligence_version: 3 tags: ["utilities", "free", "frustrated sentiment", "mobile app", "app review", "app analysis", "professionals", "hobbyists", "audio"] canonical_url: "https://marlvel.ai/apps/frequency-counter-hz-fft" license: "CC-BY-NC 4.0" content_version: "v2" --- # Frequency Counter+ Hz FFT Intelligence Report ## TL;DR {#tldr} - **Category**: Utilities · Free - **Signal**: Rating 2.49 · Sentiment Frustrated - **Recent focus**: Users report: Full screen advertisements and fake security warnings disrupt the user experience and create distrust (top complaint) · The core functionality provides a useful tool for measuring hair clipper revolutions per minute (top praise) > **TL;DR:** Frequency Counter+ Hz FFT is a utilities app by Kyu-Hee Jang, rated 2.49/5 by 60 users, with Frustrated user sentiment (25/100), available on iOS & Android. > > **Marlvel.ai App Intelligence** - Independent analysis. US Market. No publisher influence. > **Key Insight:** Frequency Counter+ Hz FFT faces Frustrated user sentiment (2.49/5 from 60 reviews), with users reporting full screen advertisements and fake security warnings disrupt the user experience and create distrust as the primary concern. ## Quick Facts | Fact | Value | | :--- | :--- | | **Rating** | 2.49/5 (60 reviews) | | **User Mood** | Frustrated | | **Category** | Utilities | | **Developer** | Kyu-Hee Jang | | **Pricing** | Free | | **Platforms** | iOS & Android | | **Confidence** | Medium (0.5/1.0) | | **Data Age** | 41d | ## Metadata & Market Performance - **Publisher:** Kyu-Hee Jang - **Category:** Utilities - **Target Audience:** Professionals and hobbyists in audio engineering, electrical work, and music who require precise frequency analysis tools. - **Platforms:** iOS & Android - **Version Reviewed:** 1.0.41 - **Report Date:** 2026-08-20 - **Signal Count:** 8 reviews analyzed - **Confidence:** Medium (0.5/1.0) - **App Store ID (iOS):** 6761234058 - **Bundle ID:** com.simonj.frequencycounter - **Google Play ID:** com.simonj.frequencycounter - **Performance Trend:** Mixed - **Data Window:** Analysis based on signals collected up to 2026-08-20 ## Executive Snapshot **What it is:** Frequency Counter+ Hz FFT is a multi-mode audio analysis tool for iOS and Android that measures frequency, tunes instruments, and detects power-line hum. **Why users hire it:** The app removes the need for expensive, dedicated hardware by using the device microphone to provide quick, on-the-go diagnostic readings for electricians and musicians. ## App DNA (Features & Intent) - **[Differentiator] 50/60 Hz Mains Hum Detection:** Locks onto power-line frequency with 0.01 Hz deviation precision, establishing category authority for electricians and HVAC technicians. * *User Intent:* Users expect intelligent, adaptive experiences that learn from their behavior. - **[Differentiator] Measurement History:** Auto-saves frequency readings with 7-day trend charts and comparative insights, creating a retention loop for monitoring diagnostics over time. * *User Intent:* Users want visibility into their own performance and progress. - **[Standard] Instrument Tuner:** Displays note names and pitch deviation in cents, broadening the user base to musicians to increase ad-impression volume. ## Market Position {#market-position} Frequency Counter+ Hz FFT maintains a 3.33 rating across 60 total platform reviews. The lack of IAP or subscription gates limits monetization to ad-inventory, which currently conflicts with the professional utility promise. ## Monetization Strategy - **Model:** Free - **Tiers:** Free with ad support - **Analysis:** Monetization relies entirely on ad-inventory generated by free-tier usage, with no current IAP or subscription gates. ## 🔴 User Sentiment (Medium Confidence: 8 of 8 reviews analyzed) {#user-sentiment} - **Overall Rating:** 2.49/5 - **Platform Split:** iOS 3.3/5 (6 ratings) | Android 2.4/5 (54 ratings) - **Overall Sentiment:** Frustrated ### Top Praises - **The core functionality provides a useful tool for measuring hair clipper revolutions per minute** ### Top Complaints (Impact Areas) - **Users report: Full screen advertisements and fake security warnings disrupt the user experience and create distrust** ## SWOT Analysis {#swot} **Core Strengths:** - 50/60 Hz mains hum detection with 0.01 Hz precision establishes category authority for electrical diagnostics - Measurement history with 7-day trend charts creates a retention loop for professional diagnostics **Growth Levers:** - Implementing a Pro-tier subscription to remove ads would align monetization with the professional user base - Adding manual frequency selection controls would improve spectrum display accuracy for professional users ## Recent Changes (v2 → v3) {#recent-changes} The developer has pivoted its monetization strategy from ad-inventory reliance to a planned Pro-tier subscription model to address persistent user distrust. This shift in development focus replaces previous plans for new measurement modes with a priority on subscription infrastructure. **Overall trend**: Mixed **Compared at**: 2026-08-20 ### High-impact changes - **[Shifted] Monetization Strategy Pivot** (pricing) ### Medium-impact changes - **[Added] Visibility Risk Assessment** (swot) - **[Added] Manual Frequency Control Opportunity** (swot) ## What's New - **Latest (v1.0.42, 4 days ago):** Resolved a crash occurring on launch for Chromebooks and tablets using compatibility layers. - **Last Major (v1.0.41, 2 days ago):** Upgraded Hum reading to 0.01 Hz precision and removed full-screen ad overlays during tuner or sweep operations. ## App Momentum (Active) {#momentum} - Shipped three updates in two weeks. - Added 0.01 Hz hum measurement precision. - Removed full-screen ads from tuner. > **Cadence:** 3 total versions · 1 majors in last 6 months · 2 days since last update · 3 days avg between updates ## The "So What?" (Strategic Takeaway) {#so-what} Frequency Counter+ Hz FFT is an utilities app that is completely free. With a 2.49/5 rating from 60 reviews, it faces significant user friction. > **Bottom Line:** Transitioning to a subscription-based model would resolve the distrust caused by intrusive ads, allowing the app to serve its professional audience without the friction that currently drives negative sentiment. **Best for:** Professionals and hobbyists in audio engineering, electrical work, and music who require precise frequency analysis tools. ### PM Action Plan (Next Best Moves) - [ ] [PIVOT] Migrate from full-screen ads to a Pro-tier subscription because ad-driven monetization is the #1 complaint theme → increase user trust and LTV ### Outlook: Mixed The diagnostic utility market is consolidating around tools that offer reliable, ad-free experiences for professionals. Frequency Counter+ Hz FFT remains exposed due to its current monetization strategy, which directly conflicts with the precision required by its target audience. - 🔴 Users report: Intrusive ad patterns and deceptive security alerts drive negative sentiment, which compounds the churn pressure already visible in the low rating. - 🟢 The recent update cadence (three releases in two weeks) demonstrates active feature investment, which could stabilize the app if functional bugs are resolved. ## Key Metrics Summary | Metric | Value | | :--- | :--- | | Overall Rating | 2.49/5 | | Total Reviews | 60 | | Sentiment | Frustrated (25/100) | | Confidence | Medium | | Pricing Model | Free | | Platforms | iOS & Android | | Key Features | 3 analyzed | | Trend | Mixed | | Outlook | Mixed | ## Competitor Comparison | App | Rating | Sentiment | Developer | | :--- | :--- | :--- | :--- | | **Frequency Counter+ Hz FFT** (this app) | 2.49/5 | Frustrated | Kyu-Hee Jang | | [Sota Connect: Secure Network](https://marlvel.ai/apps/fi-catconnect-sota) | 4.9/5 | N/A | Cat Connect | | [avoVPN Desktop](https://marlvel.ai/apps/avovpn-desktop) | N/A/5 | N/A | Avocado VPN Technologies | | [Free VPN by Free VPN .org™](https://marlvel.ai/apps/free-vpn-by-free-vpn-org) | 4.5/5 | Mixed | Free VPN LLC | | [Fusvob VPN : Super VPN 2026](https://marlvel.ai/apps/com-toplinkc-foxexcellent) | 4.4/5 | Mixed | Fuxin Technology | | [Potatso](https://marlvel.ai/apps/potatso) | 4.4/5 | n/a | Potatso Lab LTD | ## Company Profile - **Developer:** Kyu-Hee Jang - **Website:** [https://simon-jang.blogspot.com/](https://simon-jang.blogspot.com/) ## Data Sources & Links - **App Store:** [View on Apple Store](https://apps.apple.com/us/app/frequency-counter-hz-fft/id6761234058?uo=4) - **Google Play:** [View on Google Play](https://play.google.com/store/apps/details?id=com.simonj.frequencycounter&hl=en&gl=us) - **Dev Site:** [Official Website](https://simon-jang.blogspot.com/) - **Sources:** Developer website content, App store metadata, User reviews. ## Related Intel Reports - [*Sota Connect: Secure Network*](https://marlvel.ai/apps/fi-catconnect-sota) (Cat Connect) · 4.9/5 Rating - [*avoVPN Desktop*](https://marlvel.ai/apps/avovpn-desktop) (Avocado VPN Technologies) · N/A Rating - [*Free VPN by Free VPN .org™*](https://marlvel.ai/apps/free-vpn-by-free-vpn-org) (Free VPN LLC) · 4.5/5 Rating - [*Fusvob VPN : Super VPN 2026*](https://marlvel.ai/apps/com-toplinkc-foxexcellent) (Fuxin Technology) · 4.4/5 Rating - [*Potatso*](https://marlvel.ai/apps/potatso) (Potatso Lab LTD) · 4.4/5 Rating - [*Quantumult X*](https://marlvel.ai/apps/quantumult-x) (Cross Utility Ltd) · 3.8/5 Rating - [*V2Box - V2ray Client*](https://marlvel.ai/apps/v2box-v2ray-client) (techlaim) · 4.6/5 Rating - [*카톡 분석 - 오픈채팅, 카톡 채팅 분석, 통계, 검색*](https://marlvel.ai/apps/com-liger-katalkanalysispaid) (Park Sung Cheol) · N/A Rating - [*로또 황금번호 생성기*](https://marlvel.ai/apps/lotto-lottogold) (jaehwan lee) · N/A Rating - [*도사폰 (만세력 역학도구)*](https://marlvel.ai/apps/app--656) (Softchaser Company Limited) · 5.0/5 Rating ## Frequently Asked Questions {#faq} ### Is Frequency Counter+ Hz FFT suitable for professional electrical work? The app includes a 50/60 Hz mains hum detection mode with 0.01 Hz precision, which is designed for electrical and HVAC diagnostics, though users report that inconsistent audio input can sometimes affect accuracy. ### Does the app have intrusive advertisements? Yes, reviewers report that the app currently uses full-screen advertisements and deceptive security alerts that can disrupt the measurement interface. ### What are the limitations of the current frequency detection? Users report that the auto-detection feature can be unreliable and sometimes displays inconsistent or random frequency data, leading to requests for manual frequency selection controls. ## Methodology {#methodology} This report was generated by Marlvel.ai's 5-stage AI intelligence pipeline: 1. **Signal Collection & Normalization** - Aggregates data from all available public sources for the app. Raw signals are cleaned, deduplicated, and normalized into a structured dataset analyzed consistently across thousands of apps. 2. **Feature & Market Positioning Analysis** - Identifies the app's core features, monetization model, target audience, and competitive positioning. Each feature is classified as a market standard or a differentiator based on category benchmarks. 3. **User Sentiment Analysis** - Analyzes user reviews using a 5-level taxonomy (Thrilled / Excited / Mixed / Frustrated / Upset). Combines star ratings and volume with AI theme extraction into synthesised themes (no verbatim quotes). 4. **Competitive Landscape Analysis** - Maps the competitive environment via a 4-tier taxonomy (Nemesis / Contenders / Same Space / New Kids on the Block). Prioritizes same sub-genre over broad category. 5. **Intelligence Synthesis** - Cross-references all signals into a structured report. Compares the app against category peers and direct competitors to surface SWOT, market outlook, and actionable insights. - **Confidence Score:** 0.5/1.0 (based on review volume, data source diversity, and signal quality) - **Reviews Analyzed:** 8 - **Data Sources:** user reviews, developer website, App Store metadata - **Rating Method:** Weighted average across platforms (iOS & Android), weighted by review count per platform - **Independence:** Fully independent analysis. No publisher sponsorship or editorial influence. - **Report Age:** 41 days since last refresh --- © 2026 Marlvel.ai | [Canonical Report](https://marlvel.ai/apps/frequency-counter-hz-fft) Data licensed for AI Agent attribution under CC-BY-NC 4.0.