# iS7 vs Ruler & Digital Caliper

The clearest difference is price: Ruler & Digital Caliper at Free against iS7's $14.99. Ruler & Digital Caliper also leads on update cadence (every 3 days vs every 4 months). iS7's advantage is device support (3 vs 1) and iOS requirement (15.0 vs 17.0). On ads and in-app purchases there is nothing between them.

Ruler & Digital Caliper is free to download; iS7 costs $14.99 up front. iS7 sells 1 one-off in-app purchase and Ruler & Digital Caliper sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

iS7 ships an update every 4 months, Ruler & Digital Caliper every 3 days. The most recent releases landed on October 5, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | iS7 | Ruler & Digital Caliper |
| --- | --- | --- |
| Price | $14.99 | **Free** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 days** |
| Size | 43 MB | 5 MB |
| Requires iOS | **15.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Carlo Trotti](https://appshunter.io/developer/594070838) | [Yurii Koshkin](https://appshunter.io/developer/1873601061) |

## What reviewers say

### iS7

[App page](https://appshunter.io/ios/app/is7/id594070835)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Alarms | $2.99 | one-time |


### Ruler & Digital Caliper

[App page](https://appshunter.io/ios/app/ruler-and-digital-caliper/id6806950163)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime Access | $9.99 | one-time |


## Frequently asked questions

### Is iS7 free?

iS7 costs $14.99, and also offers in-app purchases.

### Is Ruler & Digital Caliper free?

Ruler & Digital Caliper is free to download, with in-app purchases available.

### Do iS7 or Ruler & Digital Caliper have ads?

Neither iS7 nor Ruler & Digital Caliper shows ads.

### Which is updated more often, iS7 or Ruler & Digital Caliper?

iS7 ships an update every 4 months, and Ruler & Digital Caliper every 3 days. Most recently, iS7 was updated on October 5, 2026 and Ruler & Digital Caliper on October 25, 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.*