# Stacks vs FlipUp

The clearest difference is in-app purchases: FlipUp at none against Stacks's 2. FlipUp also leads on update cadence (every 4 days vs every 3 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Stacks sells 2 in-app purchases, starting at $9.99 per 3 months. FlipUp asks for nothing beyond the download.

Stacks ships an update every 3 months, FlipUp every 4 days. The most recent releases landed on October 16, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | Stacks | FlipUp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/flipup-flashcards/id6751901427/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 4 days** |
| Monetization | Freemium | **Free** |
| Size | 77 MB | 14 MB |
| Requires iOS | **16.4** | 17.6 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Lewis Hoy](https://appshunter.io/developer/1812196615) | [Dexis Development](https://appshunter.io/developer/1842289966) |

## What reviewers say

### Stacks

[App page](https://appshunter.io/ios/app/stacks-language-flashcards/id6745429203)

Create flashcards from your own experiences and conversations. This app uses spaced repetition to help you remember vocabulary longer with less study. It supports over 100 languages and offers offline study capabilities.

**Highlights:** Create cards from stories and conversations, Spaced repetition system (FSRS), Offline study mode, Automatic translations, Supports over 100 languages, Romanization for select scripts, Clean, minimal interface

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Stacks+ Quarterly | $9.99 | per 3 months |
| Stacks+ Yearly | $27.99 | per year |


### FlipUp

[App page](https://appshunter.io/ios/app/flipup-flashcards/id6751901427)

Learn new material directly from your phone's lock screen using interactive widgets. Practice flashcards with simple swipes and track your mastery progress. AI can help generate focused study lists for efficient memorization.

**Highlights:** Lock screen flashcard widget, Interactive practice and answer reveal, AI-generated study lists, 5-dot mastery tracking system, Fast swipe memorization

**In-app purchases:** none


## Frequently asked questions

### Is Stacks free?

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

### Is FlipUp free?

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

### Do Stacks or FlipUp have ads?

Neither Stacks nor FlipUp shows ads.

### Which is updated more often, Stacks or FlipUp?

Stacks ships an update every 3 months, and FlipUp every 4 days. Most recently, Stacks was updated on October 16, 2026 and FlipUp on October 7, 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.*