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PRODUCT / LEARNING SYSTEM2026.09–2026.11

Tago
Voca

Follow words in context, then return through personalized practice.

INDEPENDENT PRODUCT / iOS & ANDROID

Case study by

App learning home and word detail · English UIApp learning home and word detail · English UI
App learning home and word detail · English UI
01 / CONTEXT & CONTRIBUTION

The problem.
My part in it.

Background

  • Looking up an unfamiliar word elsewhere broke the original sentence context.
  • Open-ended exploration needed a clear first lesson and a route back into daily practice.
  • Content quality, audio delivery and personal progress needed separate validation and storage.

Objective

  • Connect guided discovery, contextual word exploration, daily practice and spaced review.
  • Offer 14 topics and seven seven-day courses, with recommendations informed by level, goals and interests.

My role

  • Independently designed the learning flows and content architecture; built and tested the app with AI.
  • Owned content and audio validation, personalization, review and course progress, optional account backup, and iOS/Android releases.
02 / SYSTEM DESIGN

How it connects.

Production & device boundary
Local learning with verified content and audio deliveryPrepare content before release; fetch audio when neededLocal learning with verified content and audio deliveryPrepare content before release; fetch audio when neededCONTENT PRODUCTION & DISTRIBUTIONON-DEVICE LEARNINGNETWORK WHEN NEEDEDPackaged contentPlay audioSyncSource vocabulary — 10,635 source itemsSource vocabulary10,635 source itemsContent QA — Meaning / translation / linksContent QAMeaning / translation / linksContent package — 12,464 learning entriesContent package12,464 learning entriesAudio catalog — Pronunciation / file hashesAudio catalogPronunciation / file hashesSQLite content DB — Read-only dictionary / Bundled illustrationsSQLite content DBRead-only dictionaryBundled illustrationsDiscover · explore · review — 14 topics / daily practice / Seven seven-day coursesDiscover · explore · review14 topics / daily practiceSeven seven-day coursesLearning record DB — Reviews / course progress / Goals and interestsLearning record DBReviews / course progressGoals and interestsAudio CDN → local cache — First-play download / hash checkAudio CDN → local cacheFirst-play download / hash checkOptional account backup — Apple / Google · progress syncOptional account backupApple / Google · progress sync
Zoom for detail
Processing / data flowIteration / feedbackService / environment boundary

System diagram

100%

Drag to move · Pinch or use + / − to zoom · Arrow keys to move

01

Keep the sentence in view.

Preview an unfamiliar word with its meaning in the original sentence before continuing. Combine 14 topics with level and search; use goals and interests to rank new words without changing review rules.

02

Turn exploration into a habit.

Combine due reviews and new words in one daily session. Offer seven seven-day courses, preserve the question type when retrying mistakes, and support slow or repeated audio, sharing and course-progress backup.

03

Local learning, verified delivery.

Validate meanings, translations, pronunciation and links before release. Separate read-only SQLite content from personal records. Download audio on demand with hash checks and caching; keep account backup optional.

03 / RESULTS & SCOPE

The outcome.

12,464Learning entries
14Topics to explore
7 × 7Courses × daily lessons

November 2026 · v1.0.6, released on iOS and Android. Content and feature counts, not measured learning gains. Dictionary content and bundled illustrations work offline; audio needs a connection on first play, then uses a local cache.

Released product

Tago Voca · App Store Tago Voca · Google Play
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