# Flatness vs GYDEbook

The clearest difference is price: Flatness at Free against GYDEbook's $0.99. Flatness also leads on iOS requirement (12.0 vs 14.0). GYDEbook's advantage is update cadence (every 4 days vs every 16 months). On rating, ratings volume, ads and in-app purchases there is nothing between them.

Flatness is free to download; GYDEbook costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Flatness against 5.0 for GYDEbook. Both are backed by a comparable volume of ratings — 1 and 2 respectively.

Flatness ships an update every 16 months, GYDEbook every 4 days. The most recent releases landed on October 17, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | Flatness | GYDEbook |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/flatness/id6463624359/reviews) | [5.0 (2 ratings)](https://appshunter.io/ios/app/gydebook/id6754304074/reviews) |
| Number of ratings | 1 | **2** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 16 months | **Every 4 days** |
| Monetization | **Free** | Paid |
| Size | 61 MB | 34 MB |
| Requires iOS | **12.0** | 14.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [ACOEM Group](https://appshunter.io/developer/1495816959) | [CWSP LLC](https://appshunter.io/developer/1847771297) |

## What reviewers say

### Flatness

[App page](https://appshunter.io/ios/app/flatness/id6463624359)

This app facilitates precise rectangular flatness measurements for applications like motor and pump foundations. It guides users through the entire measurement and alignment process when connected to an AT-400 Ultimate with an M9 sensor via Bluetooth. Generate instant PDF reports of your findings directly on-site.

**Highlights:** Bluetooth connectivity, Icon-based adaptive user interface, 3D result views, Instant PDF report generation, Guided measurement process

**Features:** macOS Compatibility

**In-app purchases:** none


### GYDEbook

[App page](https://appshunter.io/ios/app/gydebook/id6754304074)

Organize personal, financial, and beneficiary details in one secure location. This tool simplifies legacy planning, offering peace of mind and easy information sharing with loved ones or executors. Securely document estate details and export information instantly.

**Highlights:** Organize personal, financial, and beneficiary information, Secure documentation of estate and beneficiary details, Email-verified login for account protection, Instant PDF export, Subscription support via Apple Pay, Seamless iPhone and iPad compatibility

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Flatness free?

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

### Is GYDEbook free?

GYDEbook costs $0.99, with no in-app purchases.

### Which has better reviews, Flatness or GYDEbook?

Flatness and GYDEbook are both rated 5.0 out of 5 on the App Store, from 1 and 2 ratings respectively.

### Do Flatness or GYDEbook have ads?

Neither Flatness nor GYDEbook shows ads.

### Which is updated more often, Flatness or GYDEbook?

Flatness ships an update every 16 months, and GYDEbook every 4 days. Most recently, Flatness was updated on October 17, 2026 and GYDEbook on October 7, 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.*