# iDesign vs Slope Calc

The clearest difference is price: iDesign at Free against Slope Calc's $0.99. iDesign also leads on update cadence (every 3 months vs every 21 months). Slope Calc's advantage is in-app purchases (none vs 3) and iOS requirement (7.0 vs 15.5). On ads and device support there is nothing between them.

iDesign is free to download; Slope Calc costs $0.99 up front. iDesign sells 3 in-app purchases, starting at $6.99 per month. Slope Calc asks for nothing beyond the download.

iDesign ships an update every 3 months, Slope Calc every 21 months. The most recent releases landed on November 1, 2026 and November 10, 2026 respectively.

## The numbers

| Metric | iDesign | Slope Calc |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | **[2.6 (87 ratings)](https://appshunter.io/ios/app/idesign/id342790226/reviews)** | — |
| Number of ratings | **87** | — |
| Positive reviews | 50.2% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 21 months |
| Monetization | Free with in-app purchases | — |
| Size | 86 MB | 1 MB |
| Requires iOS | 15.5 | **7.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [TouchAware Limited](https://appshunter.io/developer/336476151) | [Yosuke Kurashima](https://appshunter.io/developer/806702002) |

## What reviewers say

### iDesign

[App page](https://appshunter.io/ios/app/idesign/id342790226)

Create professional 2D vector drawings, illustrations, and technical designs on your iPad or iPhone. Offers precise touch-based editing with unique offset controls and a full suite of advanced tools for graphics and technical design.

**Highlights:** 2D vector drawing and design, Precise touch-based editing, Advanced path editing, Technical drawing tools, Shape libraries, Layer management, iCloud sync with XDesign

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $6.99 | per month |
| Yearly Subscription | $39.99 | per year |
| Lifetime | $79.99 | one-time |


### Slope Calc

[App page](https://appshunter.io/ios/app/slope-calc/id806701999)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is iDesign free?

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

### Is Slope Calc free?

Slope Calc costs $0.99, with no in-app purchases.

### Do iDesign or Slope Calc have ads?

Neither iDesign nor Slope Calc shows ads.

### Which is updated more often, iDesign or Slope Calc?

iDesign ships an update every 3 months, and Slope Calc every 21 months. Most recently, iDesign was updated on November 1, 2026 and Slope Calc on November 10, 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.*