# Electronic Formulator vs iMark · Image Annotation Tool

The clearest difference is update cadence: Electronic Formulator at every 9 days against iMark · Image Annotation Tool's every 2 months. iMark · Image Annotation Tool's advantage is iOS requirement (13.0 vs 26.2). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Electronic Formulator sells 1 one-off in-app purchase and iMark · Image Annotation Tool sells 4 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Electronic Formulator ships an update every 9 days, iMark · Image Annotation Tool every 2 months. The most recent releases landed on October 8, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Electronic Formulator | iMark · Image Annotation Tool |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.6 (381 ratings)](https://appshunter.io/ios/app/imark-image-annotation-tool/id1174741369/reviews)** |
| Number of ratings | — | **381** |
| Positive reviews | — | 71.7% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 9 days** | Every 2 months |
| Monetization | — | Free with in-app purchases |
| Size | 19 MB | 93 MB |
| Requires iOS | 26.2 | **13.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [iDaily Corp.](https://appshunter.io/developer/364264742) |

## What reviewers say

### Electronic Formulator

[App page](https://appshunter.io/ios/app/electronic-formulator/id675036997)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Electronic Pro | $2.99 | one-time |


### iMark · Image Annotation Tool

[App page](https://appshunter.io/ios/app/imark-image-annotation-tool/id1174741369)

Enhance and annotate images with a comprehensive set of tools. Import from your photo library, camera, or maps, and customize your markups with various styles. Easily export and share your creations.

**Highlights:** Diverse annotation tools (arrow, text, mosaic, etc.), Import from photo library, camera, and maps, Customizable color schemes and history sessions, Crop and layer management, Export with custom image size, Supports iOS Photo Extension

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Coffee | $2.99 | one-time |
| Silver Coin | $5.99 | one-time |
| Gold Coin | $14.99 | one-time |
| Coffee for Everyone | $29.99 | one-time |

**What reviewers like**

- 👍 Intuitive and easy-to-use interface
- 🎨 Comprehensive annotation tools (arrows, shapes, text, magnifier)
- 💰 Completely free with no ads
- 🎯 Powerful features for screenshot markup
- 🔧 Customizable colors and styling options

**What reviewers complain about**

- 💧 Persistent watermark on all saved images
- 🌐 Language defaults to Chinese with difficult switching
- 📝 Text size limitations on large images
- 🎨 Limited font customization options
- ⚙️ Text bubble tail control is limited

**Reported bugs**

- App crashes when using brush/pen features
- Export button hidden by system UI
- Annotations disappearing after one day
- Keyboard engagement obscures image during text input
- Magnifier tool functionality issues

**Requested features**

- Ability to remove watermark (paid option requested)
- Multiple language support with easy switching
- Filled/solid geometric shapes
- Curved arrows instead of straight only
- Multiple font selection from Google Fonts


## Frequently asked questions

### Is Electronic Formulator free?

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

### Is iMark · Image Annotation Tool free?

iMark · Image Annotation Tool is free to download, with in-app purchases available.

### Do Electronic Formulator or iMark · Image Annotation Tool have ads?

Neither Electronic Formulator nor iMark · Image Annotation Tool shows ads.

### Which is updated more often, Electronic Formulator or iMark · Image Annotation Tool?

Electronic Formulator ships an update every 9 days, and iMark · Image Annotation Tool every 2 months. Most recently, Electronic Formulator was updated on October 8, 2026 and iMark · Image Annotation Tool on October 14, 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.*