# DuoCards vs Unstoppable Influence

The clearest difference is in-app purchases: Unstoppable Influence at none against DuoCards's 11. Unstoppable Influence also leads on ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

Both are free to download. DuoCards sells 10 in-app purchases, starting at $19.99 per month. Unstoppable Influence asks for nothing beyond the download.

DuoCards ships an update monthly, Unstoppable Influence every 2 months. The most recent releases landed on October 24, 2026 and October 16, 2026 respectively.

## The numbers

| Metric | DuoCards | Unstoppable Influence |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (1.4K ratings)](https://appshunter.io/ios/app/duocards-vocabulary-builder/id1508159917/reviews)** | — |
| Number of ratings | **1.4K** | — |
| Positive reviews | 63.1% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | **Monthly** | Every 2 months |
| Monetization | Free with in-app purchases | — |
| Size | 19 MB | 35 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [DuoCards s.r.o](https://appshunter.io/developer/1508159916) | [Unstoppable 365MFR Inc](https://appshunter.io/developer/1690618103) |

## What reviewers say

### DuoCards

[App page](https://appshunter.io/ios/app/duocards-vocabulary-builder/id1508159917)

Master a new language with interactive flashcards and video courses. This app helps you build vocabulary, guess words, and track your progress across over 50 languages. Learn effectively through spaced repetition and integrated translation tools.

**Highlights:** Flashcard learning with spaced repetition, Video language courses with interactive subtitles, Integrated translator for over 50 languages, Vocabulary builder and progress tracker, Guess words and phrases to sharpen skills, Read foreign language articles

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| DuoCards Premium | $19.99 | per month |
| DuoCards Plus | $33.00 | per 3 months |
| DuoCards Premium | $34.99 | per 3 months |
| DuoCards Premium | $49.99 | per year |
| DuoCards Premium | $64.90 | per year |
| DuoCards Premium | $67.99 | per year |
| DuoCards Premium | $107.99 | per year |
| DuoCards Premium | $109.00 | per year |
| DuoCards Premium | $113.99 | per year |
| DuoCards Premium | $162.99 | per year |

**What reviewers like**

- 👍 Easy to use
- 💡 Customizable flashcards
- 🚀 Efficient learning algorithm
- 🐘 Cute mascot (Memo the mammoth)

**What reviewers complain about**

- 🐛 Bugs and crashes
- ⚠️ Unreliable server connection
- 💰 Expensive subscription
- 🤔 Confusing interface

**Reported bugs**

- App freezes and crashes
- Issues with logging in and accessing content
- Inconsistent behavior when adding new words
- Problems with video playback and subtitles

**Requested features**

- Offline mode
- More customization options
- Improved spaced repetition system
- Better integration with other language learning tools


### Unstoppable Influence

[App page](https://appshunter.io/ios/app/unstoppable-influence/id6670311784)

**In-app purchases:** none


## Frequently asked questions

### Is DuoCards free?

DuoCards is free to download, with in-app purchases available.

### Is Unstoppable Influence free?

Unstoppable Influence is free to download, with no in-app purchases.

### Do DuoCards or Unstoppable Influence have ads?

DuoCards shows ads; Unstoppable Influence does not.

### Which is updated more often, DuoCards or Unstoppable Influence?

DuoCards ships an update monthly, and Unstoppable Influence every 2 months. Most recently, DuoCards was updated on October 24, 2026 and Unstoppable Influence on October 16, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*