# OptoDrum vs 528i

The clearest difference is price: 528i at Free against OptoDrum's $4.99. 528i also leads on rating (5.0 vs 2.3) and update cadence (fortnightly vs every 3 months). OptoDrum's advantage is chart position (#150 vs unranked) and ratings volume (18 vs 3). On ads, in-app purchases and device support there is nothing between them.

528i is free to download; OptoDrum costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

528i holds the better App Store score, 5.0 against 2.3. That said, the two scores are not equally well evidenced: OptoDrum has 18 ratings behind it against 3, so its average is the more settled of the two.

OptoDrum ships an update every 3 months, 528i fortnightly. The most recent releases landed on September 10, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | OptoDrum | 528i |
| --- | --- | --- |
| Price | $4.99 | **Free** |
| Rating | [2.3 (18 ratings)](https://appshunter.io/ios/app/optodrum/id374981098/reviews) | **[5.0 (3 ratings)](https://appshunter.io/ios/app/528i/id6738430099/reviews)** |
| Number of ratings | **18** | 3 |
| Positive reviews | 30.4% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Fortnightly** |
| Monetization | Paid | **Free** |
| Best chart rank | **#150** | — |
| Size | 2 MB | 35 MB |
| Requires iOS | **10.0** | 14.0.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Linsay Associates, LLC](https://appshunter.io/developer/326305565) | [528 INNOVATIONS LLC](https://appshunter.io/developer/1780816602) |

## What reviewers say

### OptoDrum

[App page](https://appshunter.io/ios/app/optodrum/id374981098)

**Currently charting:** #150 Top Paid · Medical (US App Store)

This medical tool offers a digital alternative to traditional optokinetic drums for assessing neurological, otological, and ophthalmological conditions. It allows for easy adjustment of patterns, speed, and width, making it a convenient option for clinical use.

**Highlights:** Digital replacement for optokinetic drums, Adjustable stripe patterns, width, and speed, Five pattern types: stripes, colors, symbols, animals, Intuitive touch controls for speed and stopping, Pinch-to-zoom for pattern width adjustment

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

**In-app purchases:** none


### 528i

[App page](https://appshunter.io/ios/app/528i/id6738430099)

This app guides users through laser therapy sessions with step-by-step instructions and instructional videos. It connects to a laser device to optimize timing, frequency, and application for photobiomodulation and low-level laser therapy.

**Highlights:** Step-by-step smart guidance, Interactive instructional videos, Wavelength recommendations, Device connectivity, Precision wellness at home

**In-app purchases:** none


## Frequently asked questions

### Is OptoDrum free?

OptoDrum costs $4.99, with no in-app purchases.

### Is 528i free?

528i is free to download, with no in-app purchases.

### Which has better reviews, OptoDrum or 528i?

528i is rated higher. OptoDrum averages 2.3 out of 5 from 18 ratings, while 528i averages 5.0 from 3 ratings.

### Do OptoDrum or 528i have ads?

Neither OptoDrum nor 528i shows ads.

### Which is updated more often, OptoDrum or 528i?

OptoDrum ships an update every 3 months, and 528i fortnightly. Most recently, OptoDrum was updated on September 10, 2026 and 528i on June 1, 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.*