# FlipShadow - Flash Cards — Train Retrieval Speak Fluently

> Train Retrieval Speak Fluently (iPhone/iPad app by Jong Seon Lee.)

- Source: https://appshunter.io/ios/app/flipshadow-flash-cards/id6758394253 (this page in markdown: same URL + `.md`)
- Developer: [Jong Seon Lee](https://appshunter.io/developer/1755967230)
- Category: Education, Lifestyle
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 17.6 · 4 MB
- Languages: American English, French (France), German (Germany), Japanese, Korean, Chinese (Simplified, China), European Spanish
- Released: 2026-01-30
- Data updated: 2026-07-12
- User reviews in markdown: https://appshunter.io/ios/app/flipshadow-flash-cards/id6758394253/reviews.md

## What is FlipShadow?

Learn Languages Through Sentence Memorization

Memorizing words alone won't help you speak. Studying grammar doesn't guarantee fluency in real conversations.

Why? Because you haven't trained your brain to "retrieve" sentences.

This app combines flashcard retrieval training with a scientific spaced repetition algorithm to make memorized sentences come out naturally in conversation.


■ Key Features

▸ Flashcard Retrieval Training
Practice retrieving sentences from your brain.
Memorized sentences will automatically come out in real conversations.

▸ Scientific Spaced Repetition Algorithm (Anki-style)
Automatically calculates your optimal study schedule for efficient memorization.
Review at the perfect timing based on the forgetting curve.

▸ Choose Your Own Sentences
Memorize only the sentences you'll actually use.
Build personalized learning decks for your specific needs.

▸ Learning Statistics & Progress Tracking
Monitor your learning status with detailed statistics.
See at a glance how much you've memorized and retained.

▸ iCloud Sync
Study seamlessly across iPhone, iPad, and Mac.
Your learning progress syncs automatically across all devices.

▸ CSV File Import
Easily import your own learning materials via CSV files.
Materials created in Excel or Google Sheets work instantly.


■ Perfect For

- Those who know words but can't speak
- Those who studied grammar but struggle in real conversations
- Anyone who wants to memorize efficiently
- Anki users who found it too complex
- Learners who want to choose only useful sentences


■ Why Memorize Sentences?

Word memorization: "apple" = apple
→ "I ate an apple" doesn't come out automatically in conversation

Sentence memorization: "I ate an apple yesterday"
→ The entire sentence comes out naturally when the situation arises

When you memorize sentences, grammar, word order, and expressions stick together as chunks. This is real speaking ability.


■ What is Spaced Repetition?

A method of reviewing at optimal intervals based on the human forgetting curve.
- After 1 day → 3 days → 7 days → 14 days...

Repeating with increasing intervals converts information into long-term memory.

The app automatically calculates "today's review cards," so you just need to open the app and study every day.


■ Start Now

Experience memorized sentences coming out naturally.
Enjoy the pleasure of efficient memorization through scientific methods.

Start now.

- Terms of use
https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Lifetime Subsription | $9.99 | one-time |



## Version history (last 5 releases)

### 1.0.5 — 2026-03-03

- Added a Speech section in Settings.
  - You can pick a voice per language and preview it.
  - Download more voices from iOS Settings.

### 1.0.4 — 2026-02-25

Fixed an issue where iCloud sync would occasionally fail

### 1.0.3 — 2026-02-25

Added plus plan

### 1.0.2 — 2026-02-11

Learning View Optimization: Fixed an issue where long sentences on learning cards were being cut off. You can now read full sentences clearly without any display errors.

### 1.0.1 — 2026-02-08

Bug Fixes
  - Fixed Total time and Avg. time always showing 0s in Today's Study stats
  - Fixed Avg. time calculation to exclude logs without time data
  Improvements
  - Overall Progress card now maps directly to card states (New / Learning / Review)
  - Renamed "Study Complete" to "Review" for clarity
  - Fixed text overflow in Overall Progress card tiles

## More apps by Jong Seon Lee

- [Daily Reels - Video Diary](https://appshunter.io/ios/app/daily-reels-video-diary/id6520386070)
- [PacePal -  Cycling Computer](https://appshunter.io/ios/app/pacepal-cycling-computer/id6737474748)
- [Done!Done! - Done List](https://appshunter.io/ios/app/donedone-done-list/id6744691015)
- [Sentence - collect quotes](https://appshunter.io/ios/app/sentence-collect-quotes/id6749067440)
- [Caladium -  Plant time lapse](https://appshunter.io/ios/app/caladium-plant-time-lapse/id6749219404)
- [Dots - Who am I?](https://appshunter.io/ios/app/dots-who-am-i/id6756600291)

All apps by Jong Seon Lee: https://appshunter.io/developer/1755967230

---

*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 2026-07-12.*