# iSign vs ShelfPRO

The clearest difference is iOS requirement: iSign at 13 against ShelfPRO's 15.6. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

iSign ships an update monthly, ShelfPRO every 3 weeks. The most recent releases landed on October 7, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | iSign | ShelfPRO |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Monthly | **Every 3 weeks** |
| Size | 92 MB | 78 MB |
| Requires iOS | **13** | 15.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [A4B JOINT STOCK COMPANY](https://appshunter.io/developer/1642446175) | [NDS VIETNAM JOINT STOCK COMPANY](https://appshunter.io/developer/1501485785) |

## What reviewers say

### iSign

[App page](https://appshunter.io/ios/app/isign/id1642446173)

**Features:** macOS Compatibility

**In-app purchases:** none


### ShelfPRO

[App page](https://appshunter.io/ios/app/shelfpro/id6749603597)

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

**In-app purchases:** none


## Frequently asked questions

### Is iSign free?

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

### Is ShelfPRO free?

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

### Do iSign or ShelfPRO have ads?

Neither iSign nor ShelfPRO shows ads.

### Which is updated more often, iSign or ShelfPRO?

iSign ships an update monthly, and ShelfPRO every 3 weeks. Most recently, iSign was updated on October 7, 2026 and ShelfPRO on October 15, 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.*