# Bubble Level & Angle Finder vs Stackis RPN

The clearest difference is update cadence: Stackis RPN at every 4 days against Bubble Level & Angle Finder's every 2 months. Stackis RPN also leads on rating (5.0 vs 4.6) and monetization model (free vs freemium). Bubble Level & Angle Finder's advantage is ratings volume (20 vs 2). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Bubble Level & Angle Finder sells 3 in-app purchases, starting at $0.99 per 7 days and Stackis RPN sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Stackis RPN holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Bubble Level & Angle Finder has 20 ratings behind it against 2, so its average is the more settled of the two.

Bubble Level & Angle Finder ships an update every 2 months, Stackis RPN every 4 days. The most recent releases landed on September 19, 2026 and June 2, 2026 respectively.

## The numbers

| Metric | Bubble Level & Angle Finder | Stackis RPN |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.6 (20 ratings)](https://appshunter.io/ios/app/bubble-level-and-angle-finder/id6751485285/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/stackis-rpn/id6752929114/reviews)** |
| Number of ratings | **20** | 2 |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 4 days** |
| Monetization | Freemium | **Free** |
| Size | 102 MB | 10 MB |
| Requires iOS | **16.0** | 17.6 |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | +4 | 4+ |
| Developer | [ANDRES FELIPE SARRAZOLA VELEZ](https://appshunter.io/developer/1813243271) | [Skimra](https://appshunter.io/developer/403502071) |

## What reviewers say

### Bubble Level & Angle Finder

[App page](https://appshunter.io/ios/app/bubble-level-and-angle-finder/id6751485285)

Transform your device into a precise spirit level and angle meter. It offers instant setup, haptic feedback, and audible alerts for perfect leveling. Ideal for DIY, woodworking, and professional installations.

**Highlights:** Instant spirit level and angle meter, Precise digital readouts, Haptic and audible feedback, Customizable angle snapping, Adjustable sensitivity tolerance, Offline functionality

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Pro | $0.99 | per 7 days |
| Annual Pro | $14.99 | per year |
| Lifetime Access | $54.99 | one-time |


### Stackis RPN

[App page](https://appshunter.io/ios/app/stackis-rpn/id6752929114)

A calculator designed for users who prefer Reverse Polish Notation (RPN). It offers a familiar interface for RPN users and includes support for duodecimal calculations.

**Highlights:** RPN calculation style, Duodecimal (dozenal) support, Familiar interface for RPN users, Simple and pleasant user experience

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Advanced Mode | $1.99 | one-time |


## Frequently asked questions

### Is Bubble Level & Angle Finder free?

Bubble Level & Angle Finder is free to download, with in-app purchases available.

### Is Stackis RPN free?

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

### Which has better reviews, Bubble Level & Angle Finder or Stackis RPN?

Stackis RPN is rated higher. Bubble Level & Angle Finder averages 4.6 out of 5 from 20 ratings, while Stackis RPN averages 5.0 from 2 ratings.

### Do Bubble Level & Angle Finder or Stackis RPN have ads?

Neither Bubble Level & Angle Finder nor Stackis RPN shows ads.

### Which is updated more often, Bubble Level & Angle Finder or Stackis RPN?

Bubble Level & Angle Finder ships an update every 2 months, and Stackis RPN every 4 days. Most recently, Bubble Level & Angle Finder was updated on September 19, 2026 and Stackis RPN on June 2, 2026.

---

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