# Optogenetics Pro vs Diary Fast

The clearest difference is ads: Optogenetics Pro at none against Diary Fast's shown. Diary Fast's advantage is update cadence (every 8 days vs every 45 months) and iOS requirement (13.0 vs 17.0). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Optogenetics Pro ships an update every 45 months, Diary Fast every 8 days. The most recent releases landed on October 7, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | Optogenetics Pro | Diary Fast |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/optogenetics-pro/id641358148/reviews)** | — |
| Number of ratings | **2** | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 45 months | **Every 8 days** |
| Monetization | Free | — |
| Size | 365 MB | 69 MB |
| Requires iOS | 17.0 | **13.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Popneuron Ltd.](https://appshunter.io/developer/569968720) | [Ashore Limited](https://appshunter.io/developer/6785806448) |

## What reviewers say

### Optogenetics Pro

[App page](https://appshunter.io/ios/app/optogenetics-pro/id641358148)

This tool helps researchers calculate the necessary optical power for optogenetics experiments involving light delivery to deep brain areas. It considers brain region scattering properties, opsin type, and optical fiber characteristics to estimate excitation depth as a function of optical power.

**Highlights:** Calculate required optical power, Estimate opsin excitation depth, Model light scattering in brain tissue, Input brain region properties, Input opsin properties, Input optical fiber properties

**Features:** macOS Compatibility

**In-app purchases:** none


### Diary Fast

[App page](https://appshunter.io/ios/app/diary-fast/id6797472020)

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

**In-app purchases:** none


## Frequently asked questions

### Is Optogenetics Pro free?

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

### Is Diary Fast free?

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

### Do Optogenetics Pro or Diary Fast have ads?

Diary Fast shows ads; Optogenetics Pro does not.

### Which is updated more often, Optogenetics Pro or Diary Fast?

Optogenetics Pro ships an update every 45 months, and Diary Fast every 8 days. Most recently, Optogenetics Pro was updated on October 7, 2026 and Diary Fast on September 23, 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.*