--- schema_type: "SoftwareApplication" entity_type: "Mobile Application" app_name: "Sleep time record charts" developer_entity: "YUTAKA IZUMIYAMA" bundle_id: "tokyo.yuz.isleeptime" app_store_id: "6502098948" category: "Lifestyle" primary_platform: "ios" primary_monetization: "Free" offline_capable: false market_region: "US" platforms: "iOS" app_last_updated: "2026-06-04" report_date: "2026-07-04" last_verified: "2026-07-04T16:36:17.918Z" report_version: "26.6.26" total_reviews: 0 confidence: "low" confidence_score: 0.2 data_age_days: 12 momentum_velocity: "maintenance" intelligence_version: 3 nemesis: "Sleep as Android: Smart alarm" competitor_count: 11 tags: ["lifestyle", "free", "mobile app", "app review", "app analysis", "individuals", "seeking", "manual,"] canonical_url: "https://marlvel.ai/apps/sleep-time-record-charts" license: "CC-BY-NC 4.0" content_version: "v2" --- # Sleep time record charts App Audit ## TL;DR {#tldr} - **Category**: Lifestyle · Free > **TL;DR:** Sleep time record charts is a lifestyle app by YUTAKA IZUMIYAMA, available on iOS. > > **Marlvel.ai App Intelligence** — Independent analysis. US Market. No publisher influence. > **Key Insight:** Sleep time record charts is a lifestyle app by YUTAKA IZUMIYAMA. ## Quick Facts | Fact | Value | | :--- | :--- | | **Category** | Lifestyle | | **Developer** | YUTAKA IZUMIYAMA | | **Pricing** | Free | | **Platforms** | iOS | | **Confidence** | Low (0.2/1.0) | | **Data Age** | 12d | ## Metadata & Market Performance - **Publisher:** YUTAKA IZUMIYAMA - **Category:** Lifestyle - **Target Audience:** Individuals seeking a manual, multi-user tracking tool for sleep duration and mood correlation. - **Platforms:** iOS - **Version Audited:** 26.6.26 - **Audit Date:** 2026-07-04 - **Signal Count:** 0 reviews analyzed - **Confidence:** Low (0.2/1.0) - **App Store ID (iOS):** 6502098948 - **Bundle ID:** tokyo.yuz.isleeptime - **Performance Trend:** Stable - **Data Window:** Analysis based on signals collected up to 2026-07-04 ## Executive Snapshot **What it is:** Sleep time record charts is a manual sleep and mood logging utility for iOS that supports multi-user profiles on a single device. **Why users hire it:** Users hire this app for a low-friction, privacy-first way to track sleep without granting background sensor permissions or battery-draining automation access. ## App DNA (Features & Intent) - **[Standard] Sleep Time Calculation:** Automated duration math based on manual timestamps. - **[Differentiator] Multi-User Management:** Support for multiple user profiles on a single device. * *User Intent:* Users seek enhanced value through premium features. - **[Differentiator] Long-Press Quick Entry:** Shortcut to set current time via long-press gestures. ## Market Position {#market-position} The app occupies a minimalist niche in the Lifestyle category, prioritizing manual entry over the automated sensor-based tracking standard in the broader market. ## Monetization Strategy - **Model:** Free - **Tiers:** Free - **Analysis:** Distributed as a free utility with no visible subscription or in-app purchase gates. ## SWOT Analysis {#swot} **Core Strengths:** - Multi-user profile management enables shared-device utility - Long-press gestures reduce manual logging friction - Zero-permission architecture appeals to privacy-sensitive segments **Critical Frictions:** - Manual-only entry creates high user-effort churn - Lack of automated biometric integration limits data depth - No cloud-sync prevents cross-device data continuity **Growth Levers:** - Implement basic wearable data import to bridge the automation gap - Add export functionality for health-data portability **Market Threats:** - Automated sensor-based trackers continue to lower the barrier to entry - Habit-gamification apps capture the casual-user segment ## Recent Changes (v2 → v3) {#recent-changes} The app has refined its competitive positioning to emphasize privacy and zero-permission architecture while pivoting development resources toward data portability. **Overall trend**: Stable **Compared at**: 2026-07-04 ### High-impact changes - **[Shifted] Privacy-First Positioning** (positioning) — The narrative shifted from a general manual-tracking utility to a specific privacy-focused tool that rejects background sensor permissions. - **[Shifted] PM Action Item Pivot** (positioning) — Prioritized CSV data export over UI layout updates to address the lack of data portability. ### Medium-impact changes - **[Added] New SWOT Items** (swot) — Added 'Zero-permission architecture' as a strength, 'No cloud-sync' as a weakness, and 'Export functionality' as an opportunity. - **[Added] Cloud-Sync Feature Gap** (features) — Added 'Cloud-sync for cross-device data continuity' to the list of feature gaps. ## Rivals Landscape {#rivals} > Competitive positioning identified by AI analysis of app features, category, and market signals. ### Sleep time record charts vs Sleep as Android: Smart alarm — Head to Head - **[Sleep as Android: Smart alarm](https://marlvel.ai/apps/sleep-as-android-smart-alarm)** by Petr Nálevka (Urbandroid): This app is the primary nemesis because it dominates the sleep tracking category with advanced sensor-based automation, directly challenging the manual logging approach of the target app. - **Key differences:** - Utilizes sonar and AI sound recognition for automated tracking, eliminating the need for manual bedtime input. - Features complex CAPTCHA alarm tasks that force user engagement, significantly increasing utility over simple logging tools. - Offers a massive ecosystem of integrations and long-term data analytics that create high user switching costs. - **Where Sleep time record charts wins:** - ✅ Provides a frictionless, low-complexity interface for users who find automated tracking intrusive or battery-draining. - ✅ Offers a simplified, manual-first workflow that appeals to users seeking privacy without background sensor permissions. - **Where Sleep as Android: Smart alarm wins:** - ❌ Delivers sophisticated, data-driven sleep insights through automated sensor technology that the target app lacks entirely. - ❌ Maintains a massive, established user base and high-frequency update cadence that ensures long-term platform relevance. - **Verdict:** The target app should pivot toward a 'minimalist manual logger' niche, as it cannot compete with the feature depth of Sleep as Android. ### Contenders (Strong Challengers) - **[Early Bed - Record bedtime](https://marlvel.ai/apps/early-bed-record-bedtime)** by 翔宇 孟: A direct functional competitor that mirrors the target app's core value proposition of manual bedtime logging and habit tracking. - Includes biological clock regulation tools that provide a more structured approach to habit formation than simple charts. - Offers high-fidelity sleep sounds to assist with the bedtime routine, adding value beyond basic data recording. - **[Sleep Tracker & Sound by Remly](https://marlvel.ai/apps/com-visionwizard-sleeptrack)** by DEEP FLOW SOFTWARE SERVICES: Directly competes by combining sleep logging with environmental soundscapes and physiological data, offering a more comprehensive nighttime experience. - Provides a built-in sleep environment mixer, allowing users to customize audio landscapes for better sleep onset. - Captures heart rate and breathwork data to provide a more clinical view of sleep health than manual charts. - **[MoMoSleep - Auto Sleep Tracker](https://marlvel.ai/apps/momosleep-auto-sleep-tracker)** by ScicoDream Network Technology Ltd: Challenges the target app by gamifying the sleep experience and enforcing behavioral habits through app-locking features. - Implements an 'Early Sleep App Lock' to actively prevent late-night phone usage, a proactive behavioral intervention. - Uses 'Dream Café' gamification elements to increase daily retention compared to the target's purely functional logging. - **[Glory Ring](https://marlvel.ai/apps/glory-ring)** by Shenzhen Ultra Easy Technology Co., Ltd.: Competes by bundling sleep analysis with hardware-specific smart ring data, shifting the value proposition from manual entry to passive biometric monitoring. - Integrates directly with wearable smart ring hardware to provide passive, objective sleep quality metrics. - Focuses on holistic health data display, positioning sleep tracking as one component of a broader fitness ecosystem. ### Peers (What They Do Better) - **[Somryst](https://marlvel.ai/apps/somryst)** by KOEO: Targets the clinical sleep market, offering a structured program that makes simple logging apps feel like basic utilities. - Delivers a clinically validated digital CBT-I program, positioning the app as a medical treatment rather than a tracker. - Provides professional clinical progress tracking, creating a high barrier to entry for non-medical lifestyle apps. - **[Silent-Night - Anti Snoring](https://marlvel.ai/apps/silent-night-anti-snoring)** by Mobile Box - App Consulting UG (haftungsbeschraenkt): Occupies the medical-adjacent sleep space, focusing on specific sleep quality interventions rather than general logging. - Uses active vibration-based snore intervention to provide a tangible, corrective solution to sleep disturbances. - Processes all data on-device, appealing to users with strict requirements for medical data privacy and security. - **[Thunderstorm Sounds for Sleeps](https://marlvel.ai/apps/thunderstorm-sounds-for-sleeps)** by Muhammed Asaad Nadeem: Competes for the same 'pre-sleep' user attention by providing specialized audio tools for sleep induction. - Specializes in granular noise variations like fan simulations, catering to specific user preferences for white noise. - Includes meditation support, broadening the app's utility to include mindfulness practices alongside sleep preparation. - **[Sleep Sounds Offline - Relax](https://marlvel.ai/apps/sleep-sounds-offline-relax)** by Elsa George: Shares the lifestyle category by focusing on the auditory environment of sleep rather than the data tracking aspect. - Focuses exclusively on customizable audio themes, serving users who prioritize relaxation over quantitative sleep analysis. - Operates entirely offline, providing a privacy-focused, low-bandwidth alternative to data-heavy tracking applications. ### New Kids on the Block (What's Innovative) - **[Symtraq - Symptom Tracker](https://marlvel.ai/apps/symtraq-symptom-tracker)** by Softpulse Infotech: A new health-tracking app that overlaps with the target's user base by offering comprehensive daily logging and journaling. - Combines symptom, mood, and medication tracking into a single, unified interface for holistic personal health monitoring. - **[Exoda Food Calories Recipes](https://marlvel.ai/apps/exoda-food-calories-recipes)** by Tobias Stephan: A new entrant in the health space that competes for the same user's daily health-tracking attention span. - Integrates with Open Food Facts to provide a comprehensive nutrition diary, diversifying the user's health data portfolio. ## What's New - **Latest (v26.6.26, 4 weeks ago):** Updated app screen layout. ## App Momentum (Maintenance) {#momentum} - Maintains manual-first logging utility. - Supports multi-user profile management. > **Cadence:** 1 total versions · 0 majors in last 6 months · 29 days since last update ## The "So What?" (Strategic Takeaway) {#so-what} Sleep time record charts is an established lifestyle app that is completely free. > **Bottom Line:** Sleep time record charts succeeds as a minimalist, privacy-focused utility, but its manual-only design limits its appeal against automated competitors, so the team must prioritize data portability to retain power users who outgrow basic logging. **Best for:** Individuals seeking a manual, multi-user tracking tool for sleep duration and mood correlation. ### PM Action Plan (Next Best Moves) - [ ] [INVEST] [HIGH IMPACT] Ship CSV data export because users lack data portability → unlock long-term retention for power users — *Manual logging apps require data portability to retain users who eventually move to more advanced tracking tools.* _(trade-off: deprioritize Pause the UI-refresh sprint; export is a higher-value utility for the current user base.)_ - [ ] [PIVOT] [MEDIUM IMPACT] Audit the manual-entry flow for potential automation hooks because manual logging is the primary churn risk → reduce daily friction — *Competitors like Sleep as Android remove manual entry entirely, creating a massive utility gap.* _(trade-off: deprioritize Deprioritize the multi-user edit features; the core logging flow needs more immediate attention.)_ ### Feature Gaps vs Competitors - Automated sensor-based tracking (available in Sleep as Android but absent here) - Cloud-sync for cross-device data continuity (available in Sleep as Android but absent here) ### Outlook: Stable The sleep-tracking market is consolidating around automated, biometric-integrated solutions, leaving manual loggers in a shrinking niche. The app's future depends on serving the privacy-conscious segment that rejects these automated tools, so the PM must focus on data portability to keep these users from migrating to more comprehensive platforms. - ⚪ The app maintains a stable, manual-first feature set, avoiding the feature bloat that complicates more complex sleep-tracking applications. - 🔴 The lack of automated data entry creates a widening utility gap against sensor-based rivals, which will likely accelerate churn among casual users. ## Key Metrics Summary | Metric | Value | | :--- | :--- | | Total Reviews | 0 | | Confidence | Low | | Pricing Model | Free | | Platforms | iOS | | Key Features | 3 analyzed | | Trend | Stable | | Outlook | Stable | ## Competitor Comparison | App | Rating | Sentiment | Developer | | :--- | :--- | :--- | :--- | | **Sleep time record charts** (this app) | N/A/5 | N/A | YUTAKA IZUMIYAMA | | [Sleep Tracker & Sound by Remly](https://marlvel.ai/apps/com-visionwizard-sleeptrack) | 4.8/5 | Frustrated | DEEP FLOW SOFTWARE SERVICES | | [Sleep as Android: Smart alarm](https://marlvel.ai/apps/sleep-as-android-smart-alarm) | 4.6/5 | Excited | Petr Nálevka (Urbandroid) | | [Silent-Night - Anti Snoring](https://marlvel.ai/apps/silent-night-anti-snoring) | 1.0/5 | Frustrated | Mobile Box - App Consulting UG (haftungsbeschraenkt) | | [Exoda Food Calories Recipes](https://marlvel.ai/apps/exoda-food-calories-recipes) | N/A/5 | N/A | Tobias Stephan | | [Sleep Sounds Offline - Relax](https://marlvel.ai/apps/sleep-sounds-offline-relax) | 5.0/5 | N/A | Elsa George | ## Company Profile - **Developer:** YUTAKA IZUMIYAMA - **Website:** [https://z-wg.com/sleep-time-charts/](https://z-wg.com/sleep-time-charts/) ## Data Sources & Links - **App Store:** [View on Apple Store](https://apps.apple.com/us/app/sleep-time-record-charts/id6502098948?uo=4) - **Dev Site:** [Official Website](https://z-wg.com/sleep-time-charts/) - **Sources:** Developer website content, App store metadata. ## Related Intel Reports - [*Sleep Tracker & Sound by Remly*](https://marlvel.ai/apps/com-visionwizard-sleeptrack) (DEEP FLOW SOFTWARE SERVICES) — 4.8/5 Rating | Negative Sentiment - [*Sleep as Android: Smart alarm*](https://marlvel.ai/apps/sleep-as-android-smart-alarm) (Petr Nálevka (Urbandroid)) — 4.6/5 Rating | Positive Sentiment - [*Silent-Night - Anti Snoring*](https://marlvel.ai/apps/silent-night-anti-snoring) (Mobile Box - App Consulting UG (haftungsbeschraenkt)) — 1.0/5 Rating | Negative Sentiment - [*Exoda Food Calories Recipes*](https://marlvel.ai/apps/exoda-food-calories-recipes) (Tobias Stephan) — N/A Rating | N/A Sentiment - [*Sleep Sounds Offline - Relax*](https://marlvel.ai/apps/sleep-sounds-offline-relax) (Elsa George) — 5.0/5 Rating | N/A Sentiment - [*Thunderstorm Sounds for Sleeps*](https://marlvel.ai/apps/thunderstorm-sounds-for-sleeps) (Muhammed Asaad Nadeem) — 4.5/5 Rating | N/A Sentiment - [*Symtraq - Symptom Tracker*](https://marlvel.ai/apps/symtraq-symptom-tracker) (Softpulse Infotech) — N/A Rating | N/A Sentiment - [*Glory Ring*](https://marlvel.ai/apps/glory-ring) (Shenzhen Ultra Easy Technology Co., Ltd.) — 5.0/5 Rating | N/A Sentiment - [*Early Bed - Record bedtime*](https://marlvel.ai/apps/early-bed-record-bedtime) (翔宇 孟) — N/A Rating | N/A Sentiment - [*Somryst*](https://marlvel.ai/apps/somryst) (KOEO) — 3.2/5 Rating | Mixed Sentiment ## 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 and evidence quoting. 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:** 0.2/1.0 (based on review volume, data source diversity, and signal quality) - **Reviews Analyzed:** 0 - **Data Sources:** 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:** 12 days since last refresh --- © 2026 Marlvel.ai | [Canonical Report](https://marlvel.ai/apps/sleep-time-record-charts) Data licensed for AI Agent attribution under CC-BY-NC 4.0.