# Curvature vs Octopus Watch

The clearest difference is rating: Curvature at 5.0 against Octopus Watch's 4.0. Curvature also leads on review sentiment (100% vs 65%) and in-app purchases (none vs 2). Octopus Watch's advantage is update cadence (every 3 weeks vs every 5 months). On price, ratings volume, ads and device support there is nothing between them.

Curvature costs $1.99 and Octopus Watch $1.99 up front. Octopus Watch sells 2 in-app purchases, starting at $1.99 per month. Curvature asks for nothing beyond the download.

Curvature holds the better App Store score, 5.0 against 4.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively. Written reviews point the same way: 100% of Curvature's written reviews are positive against 65% of Octopus Watch's.

Curvature ships an update every 5 months, Octopus Watch every 3 weeks. The most recent releases landed on October 24, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Curvature | Octopus Watch |
| --- | --- | --- |
| Price | $1.99 | $1.99 |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/curvature/id1441050109/reviews)** | [4.0 (1 ratings)](https://appshunter.io/ios/app/octopus-watch/id1490260614/reviews) |
| Number of ratings | **2** | 1 |
| Positive reviews | **100.0% of reviews** | 64.6% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 116 MB | 19 MB |
| Requires iOS | 17.6 | **16.1** |
| Devices | iPhone, iPad | **iPhone, iPad, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Steven Wilkinson](https://appshunter.io/developer/1441050108) | [Kim Bauters](https://appshunter.io/developer/1451850103) |

## What reviewers say

### Curvature

[App page](https://appshunter.io/ios/app/curvature/id1441050109)

This app provides advanced tools for calculating and visualizing earth measurements, including curvature, horizon distance, and drop distance. It features a redesigned interface with precision mapping, data persistence, and a knowledge hub with research resources.

**Highlights:** Advanced Earth Calculators, Graphic Result Visualization, Precision Mapping Tools, Data Persistence with SwiftData, Expanded PDF Library, Universal Unit Converter, Save & Export Calculations

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

**In-app purchases:** none


### Octopus Watch

[App page](https://appshunter.io/ios/app/octopus-watch/id1490260614)

Easily manage your Octopus Energy tariffs, track electricity rates, and identify optimal times to use appliances or charge your EV. Offers insights into usage, weather impacts, and export earnings. Optional subscription unlocks advanced features like 48-hour rate predictions and carbon integration.

**Highlights:** Track current and upcoming electricity rates, Identify cheapest times for appliances/EV charging, View historic usage and micro metrics, Receive rate change alerts, Compare tariffs, Export data to CSV, 48h Agile rate predictions (subscription)

**Features:** Family Sharing, Apple Watch app, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Month Subscription | $1.99 | per month |
| 1 Year Subscription | $11.99 | per year |


## Frequently asked questions

### Is Curvature free?

Curvature costs $1.99, with no in-app purchases.

### Is Octopus Watch free?

Octopus Watch costs $1.99, and also offers in-app purchases.

### Which has better reviews, Curvature or Octopus Watch?

Curvature is rated higher. Curvature averages 5.0 out of 5 from 2 ratings, while Octopus Watch averages 4.0 from 1 ratings.

### Do Curvature or Octopus Watch have ads?

Neither Curvature nor Octopus Watch shows ads.

### Which is updated more often, Curvature or Octopus Watch?

Curvature ships an update every 5 months, and Octopus Watch every 3 weeks. Most recently, Curvature was updated on October 24, 2026 and Octopus Watch on October 29, 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.*