# Pocket Slide Rule Expert vs Atomic Spectra

The clearest difference is update cadence: Pocket Slide Rule Expert at every 4 months against Atomic Spectra's every 19 months. Pocket Slide Rule Expert also leads on chart position (#183 vs unranked) and ratings volume (4 vs 1). Atomic Spectra's advantage is rating (5.0 vs 4.8) and review sentiment (100% vs 83%). On ads, in-app purchases and monetization model there is nothing between them.

Pocket Slide Rule Expert costs $0.99 and Atomic Spectra $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Atomic Spectra holds the better App Store score, 5.0 against 4.8. Both are backed by a comparable volume of ratings — 4 and 1 respectively. Written reviews point the same way: 83% of Pocket Slide Rule Expert's written reviews are positive against 100% of Atomic Spectra's.

Pocket Slide Rule Expert ships an update every 4 months, Atomic Spectra every 19 months. The most recent releases landed on November 6, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Pocket Slide Rule Expert | Atomic Spectra |
| --- | --- | --- |
| Price | **$0.99** | $1.99 |
| Rating | [4.8 (4 ratings)](https://appshunter.io/ios/app/pocket-slide-rule-expert/id434331277/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/atomic-spectra/id6444901660/reviews)** |
| Number of ratings | **4** | 1 |
| Positive reviews | 83.3% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 19 months |
| Monetization | Paid | Paid |
| Best chart rank | **#183** | — |
| Size | 16 MB | 7 MB |
| Requires iOS | **9.0** | 26.0 |
| Devices | iPhone, iPod | **iPhone, iPad, Mac, Apple TV** |
| Age rating | 4+ | 4+ |
| Developer | [TestTubeGames](https://appshunter.io/developer/421890276) | [Jim Haungs](https://appshunter.io/developer/1498282259) |

## What reviewers say

### Pocket Slide Rule Expert

[App page](https://appshunter.io/ios/app/pocket-slide-rule-expert/id434331277)

**Currently charting:** #183 Top Paid · Education (US App Store)

Learn to use a classic slide rule with this app. It offers precise calculations and an "auto-slide-rule" mode to demonstrate operations. Save and reuse slider positions for frequent calculations.

**Highlights:** Classic slide rule simulation, Auto-slide-rule demonstration mode, Precise cursor and slider control, Save and reuse slider positions ('Snaps'), 19 basic operations supported, Multiplication, division, powers, logs, trig functions

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

**In-app purchases:** none


### Atomic Spectra

[App page](https://appshunter.io/ios/app/atomic-spectra/id6444901660)

This reference app provides detailed information on strong line atomic emission spectra within the visible range. Users can search for elements by name, symbol, or atomic number and inspect individual spectra lines. It offers interactive features to visualize and navigate spectral data.

**Highlights:** Visible range spectra (380-740nm), Search by element name, symbol, or atomic number, Sort by name, symbol, or spectra line count, Inspect individual spectra lines, Interactive spectrum visualization

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Pocket Slide Rule Expert free?

Pocket Slide Rule Expert costs $0.99, with no in-app purchases.

### Is Atomic Spectra free?

Atomic Spectra costs $1.99, with no in-app purchases.

### Which has better reviews, Pocket Slide Rule Expert or Atomic Spectra?

Atomic Spectra is rated higher. Pocket Slide Rule Expert averages 4.8 out of 5 from 4 ratings, while Atomic Spectra averages 5.0 from 1 ratings.

### Do Pocket Slide Rule Expert or Atomic Spectra have ads?

Neither Pocket Slide Rule Expert nor Atomic Spectra shows ads.

### Which is updated more often, Pocket Slide Rule Expert or Atomic Spectra?

Pocket Slide Rule Expert ships an update every 4 months, and Atomic Spectra every 19 months. Most recently, Pocket Slide Rule Expert was updated on November 6, 2026 and Atomic Spectra on November 3, 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.*