Zenolab.app
Learn Japanese - Pidu: AI Chat Practice & JLPT N5-N1 Drills
Added AI-powered conversation practice using on-device NLP. Users can now simulate real Japanese dialogues and get instant feedback on grammar and vocabulary.
Zenolab · One-person studio
Small apps.
Made with care.
Zenolab is a one-person studio. I'm Truong — I design, build, and maintain every app here, and I answer every email myself.
Dual: Front & Back Recorder Photo & Video 
Remote for Smart TV & Box Utilities 
Elingo: Learn 24 Languages Education 
GenCeleb: AI Celeb Photo Photo & Video 
Doodle – Draw on Photos Photo & Video 
Pidu: Learn Chinese HSK 1-6 Education 
Pixel Habit: Habit Tracker Lifestyle 
Japanese Food: Healthy Recipes Lifestyle 
PackView | Packing Checklist Productivity 
Learn Japanese: AI Tutor Pidu Education Products
Apps for the small rituals.
Dual: Front & Back Recorder
Dual Camera Video Recorder. Record front and rear cameras simultaneously.
Details Elingo: Learn 24 Languages
Learn 24 Languages – Quizzes & Multiplayer Battles. Fluency made into a game.
Details GenCeleb: AI Celeb Photo
AI Celeb Photo – Selfies, Videos & MovieSet Scenes. Pose with any celebrity.
Details Doodle – Draw on Photos
Draw on Photos – Brushes, Text & Stickers. Turn any photo into your canvas.
Details Pidu: Learn Chinese HSK 1-6
HSK 1-6 – Learn to read, flash cards. Learn Chinese, reading practice, and flashcards.
Details Pixel Habit: Habit Tracker
Habit Tracker – GitHub-Style Streak Grids. Build habits like code contributions.
Details PackView | Packing Checklist
Packing Checklist – Lock Screen List Widget. Your packing list on your lock screen.
Details Learn Japanese: AI Tutor Pidu
AI Tutor for Japanese – JLPT prep, AI chat & daily lessons. From beginner to JLPT.
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IBMath: IB Math AA & AI
IBDP Exam Practice – IB Math AA & AI, SL and HL. Skill trees, practice sets, and an AI tutor.
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SnoozeLog Snore Recorder
Snore Recorder, AI Sleep & Snore Tracking. Sleep and snore tracking with AI.
Details
DailyDot - Life Calendar
Life Calendar – AI Habits, Milestones & Reflection. See your life journey at a glance.
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Liquid Focus - Pomodoro Timer
Pomodoro Timer, Focus Timer & Study Tracker. Focus timer and study tracker.
Details
Vintage Camera - Vinx
Vintage Camera – Soulful Film Emulation. Film-like photos straight from your iPhone.
Details
Sleep Sounds & Focus: Sleepie
Sleep Sounds, Stories & Meditations – Smart Alarm. Bedtime stories, sounds, and meditations.
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ProScan: PDF Scanner & Manager
PDF Scanner & OCR – Scan, Edit & Export Documents. Your ultimate scanning companion.
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Focus Timer - PiduGo
Gamified Focus Timer – Acorn-Gathering Adventures. Stay focused as a squirrel in a forest.
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HealthLog: Blood Sugar
Simple Glucose Tracking – Large Text & Caregiver Sharing. One-tap blood sugar logging.
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Happy day: Daily Mood Tracker
Daily mood tracker and simple emo diary to understand your emotional wellbeing.
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Sleep Tracker: Forest Aura
Sleep sounds, rain & thunder with sleep tracking to understand your sleep cycles.
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MOJiKana: Learn Japanese
Hiragana, Katakana & Kanji with vocabulary, news and podcasts for all levels.
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Pomodoro Focus Timer — Molip
Minimalist Pomodoro focus timer with app blocking, labels, and focus insights.
DetailsBy the numbers
23
apps on the App Store — every one designed, coded, and shipped solo.
2
platforms cared for every week: iOS and Android.
1
person on the entire team — design, code, support, marketing.
Ship log
View allLearn Japanese - Pidu Hits the App Store
Launched our comprehensive Japanese learning app covering Kanji, Hiragana, Katakana with JLPT prep from N5 to N1. Includes daily lessons and spaced repetition flashcards.
Pidu Japanese: Designing the Spaced Repetition Algorithm
Implemented a custom SRS algorithm tuned for Japanese character recognition. Review intervals adapt based on stroke complexity and user accuracy history.
MOJiKana Update: Japanese News Reader & Podcast Player
Shipped an integrated Japanese news feed with furigana annotations and a curated podcast section. Users can now immerse in native content while building vocabulary.
Have an idea that needs a pair of hands?
I take on one freelance project per quarter — or we can simply talk shop about indie life.
Email me