# InkDeck vs Arbitrary Triangle PRO

The clearest difference is price: InkDeck at Free against Arbitrary Triangle PRO's $2.99. InkDeck also leads on update cadence (every 9 days vs every 3 weeks). Arbitrary Triangle PRO's advantage is rating (5.0 vs 4.0) and in-app purchases (none vs 3). On ratings volume, ads, device support and iOS requirement there is nothing between them.

InkDeck is free to download; Arbitrary Triangle PRO costs $2.99 up front. InkDeck sells 3 in-app purchases, starting at $2.99 per month. Arbitrary Triangle PRO asks for nothing beyond the download.

Arbitrary Triangle PRO holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

InkDeck ships an update every 9 days, Arbitrary Triangle PRO every 3 weeks. The most recent releases landed on September 18, 2026 and September 17, 2026 respectively.

## The numbers

| Metric | InkDeck | Arbitrary Triangle PRO |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | [4.0 (1 ratings)](https://appshunter.io/ios/app/inkdeck-flashcards/id1602851047/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/arbitrary-triangle-pro/id1617819308/reviews)** |
| Number of ratings | 1 | 1 |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 9 days** | Every 3 weeks |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 18 MB | 182 MB |
| Requires iOS | 16.0 | **15.0** |
| Devices | iPhone, iPad, Mac | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Muhammad Mukhtar](https://appshunter.io/developer/1515029563) | [Glindemann, Sennoun, Langer GbR](https://appshunter.io/developer/1024972809) |

## What reviewers say

### InkDeck

[App page](https://appshunter.io/ios/app/inkdeck-flashcards/id1602851047)

Create and study flashcards with handwritten notes and drawings. Supports spaced repetition, multiple study modes, and engaging games to make learning fun. Syncs across devices via iCloud without an account.

**Highlights:** Handwritten notes and drawings, Spaced repetition system, Multiple study modes (Quiz, Typing, Match), Four built-in study games, Import Anki and CSV decks, Progress tracking and stats, iCloud sync across devices

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| App Access For 1 Month | $2.99 | per month |
| App Access For 1 Year | $24.99 | per year |
| Unlimited cards | $7.99 | one-time |


### Arbitrary Triangle PRO

[App page](https://appshunter.io/ios/app/arbitrary-triangle-pro/id1617819308)

This app calculates all unknown quantities of an arbitrary triangle. It displays the formulas used and provides step-by-step solutions, supporting decimals and fractions. Calculations are saved in history and can be shared.

**Highlights:** Calculates all triangle quantities, Displays formulas used, Step-by-step solutions, Supports decimals and fractions, Calculation history, Shareable solutions

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

**In-app purchases:** none


## Frequently asked questions

### Is InkDeck free?

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

### Is Arbitrary Triangle PRO free?

Arbitrary Triangle PRO costs $2.99, with no in-app purchases.

### Which has better reviews, InkDeck or Arbitrary Triangle PRO?

Arbitrary Triangle PRO is rated higher. InkDeck averages 4.0 out of 5 from 1 ratings, while Arbitrary Triangle PRO averages 5.0 from 1 ratings.

### Do InkDeck or Arbitrary Triangle PRO have ads?

Neither InkDeck nor Arbitrary Triangle PRO shows ads.

### Which is updated more often, InkDeck or Arbitrary Triangle PRO?

InkDeck ships an update every 9 days, and Arbitrary Triangle PRO every 3 weeks. Most recently, InkDeck was updated on September 18, 2026 and Arbitrary Triangle PRO on September 17, 2026.

---

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