# CrowdMag vs Polar Scope Align

The clearest difference is review sentiment: Polar Scope Align at 91% against CrowdMag's 53%. Polar Scope Align also leads on rating (4.7 vs 4.3) and ratings volume (171 vs 24). CrowdMag's advantage is in-app purchases (none vs 3) and ads (none vs shown). On price, update cadence and device support there is nothing between them.

Both are free to download. Polar Scope Align sells 3 one-off in-app purchases. CrowdMag asks for nothing beyond the download.

Polar Scope Align holds the better App Store score, 4.7 against 4.3. That said, the two scores are not equally well evidenced: Polar Scope Align has 171 ratings behind it against 24, so its average is the more settled of the two. Written reviews point the same way: 53% of CrowdMag's written reviews are positive against 91% of Polar Scope Align's.

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on September 22, 2026 and September 8, 2026 respectively.

## The numbers

| Metric | CrowdMag | Polar Scope Align |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.3 (24 ratings)](https://appshunter.io/ios/app/crowdmag/id910578825/reviews) | **[4.7 (171 ratings)](https://appshunter.io/ios/app/polar-scope-align/id970157965/reviews)** |
| Number of ratings | 24 | **171** |
| Positive reviews | 52.9% of reviews | **91.2% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 18 MB | 23 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [University of Colorado Boulder](https://appshunter.io/developer/972210292) | [Dimitrios Kechagias](https://appshunter.io/developer/970157964) |

## What reviewers say

### CrowdMag

[App page](https://appshunter.io/ios/app/crowdmag/id910578825)

This app allows users to measure and contribute to scientific research on Earth's magnetic field using their smartphone. It offers features for recording magnetic data during various activities, including flights, and provides tools for data visualization and analysis.

**Highlights:** Measure magnetic field data, Contribute to scientific research, Record data during flights, Visualize data on maps and graphs, Magnetic calculator with WMM2020, Live magnetic compass, Export data via email/Google Drive

**Features:** macOS Compatibility

**In-app purchases:** none


### Polar Scope Align

[App page](https://appshunter.io/ios/app/polar-scope-align/id970157965)

This app calculates the precise position of celestial poles in your telescope's polar scope reticle for accurate alignment. It supports a wide range of reticles and corrects for atmospheric refraction, offering precision even at lower latitudes. Features include night mode, moon phase, and astronomical databases.

**Highlights:** Polaris/Sigma Octantis position calculation, Atmospheric refraction correction, Reticle centering error correction, Supports numerous reticle types, Red-color night mode, Moon phase and astronomical databases

**Features:** Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Tip 1x | $0.99 | one-time |
| Tip 4x | $3.99 | one-time |
| Tip 10x | $9.99 | one-time |

**What reviewers like**

- 🎯 Extensive reticle options for various telescope mounts
- 👍 User-friendly and intuitive interface
- 🆓 Powerful free version with no popup ads
- 🔴 Red night vision mode preserves dark adaptation
- 📍 Accurate GPS-based location detection

**What reviewers complain about**

- 🐛 Inconsistent accuracy with metal mounts/tripods
- 📱 Font size too small for comfortable reading
- 🎯 Center dot in reticle obscures precise alignment
- 📍 Limited effectiveness for southern hemisphere (Sigma Octantis is dim)
- ❓ Steep learning curve for beginners without proper guidance

**Reported bugs**

- Date and time dial do not match correctly
- GMT and LST times appear to be switched
- App crashes or fails to initialize for some users
- Alignment accuracy varies inconsistently between sessions
- Location detection issues with cell tower vs GPS

**Requested features**

- Online video tutorials demonstrating all features
- Remove or reduce center dot size in reticle
- Larger, bolder font options for better readability
- Brighter star options for southern hemisphere alignment
- Smaller ad button or ad customization


## Frequently asked questions

### Is CrowdMag free?

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

### Is Polar Scope Align free?

Polar Scope Align is free to download, with in-app purchases available.

### Which has better reviews, CrowdMag or Polar Scope Align?

Polar Scope Align is rated higher. CrowdMag averages 4.3 out of 5 from 24 ratings, while Polar Scope Align averages 4.7 from 171 ratings.

### Do CrowdMag or Polar Scope Align have ads?

Polar Scope Align shows ads; CrowdMag does not.

### Which is updated more often, CrowdMag or Polar Scope Align?

CrowdMag ships an update every 2 months, and Polar Scope Align every 2 months. Most recently, CrowdMag was updated on September 22, 2026 and Polar Scope Align on September 8, 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.*