# Readback vs Cost Index

The clearest difference is rating: Cost Index at 5.0 against Readback's 2.3. Cost Index also leads on in-app purchases (none vs 5) and device support (3 vs 1). Readback's advantage is update cadence (every 6 months vs every 16 months) and ratings volume (8 vs 1). On price and ads there is nothing between them.

Both are free to download. Readback sells 5 one-off in-app purchases. Cost Index asks for nothing beyond the download.

Cost Index holds the better App Store score, 5.0 against 2.3. That said, the two scores are not equally well evidenced: Readback has 8 ratings behind it against 1, so its average is the more settled of the two.

Readback ships an update every 6 months, Cost Index every 16 months. The most recent releases landed on October 3, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | Readback | Cost Index |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.3 (8 ratings)](https://appshunter.io/ios/app/readback/id593334194/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/cost-index/id671845599/reviews)** |
| Number of ratings | **8** | 1 |
| Positive reviews | 57.1% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 6 months** | Every 16 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 29 MB | 3 MB |
| Requires iOS | 12.0 | **8.0** |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Santiago Borja Lopez](https://appshunter.io/developer/581569234) | [Flight Efficiency Limited](https://appshunter.io/developer/466443228) |

## What reviewers say

### Readback

[App page](https://appshunter.io/ios/app/readback/id593334194)

Streamline your air traffic control note-taking with this utility. Quickly record clearances and updates, eliminating the need for a physical scratchpad. Maintain a comprehensive log of all your flight information for better organization.

**Highlights:** Quickly capture ATC clearances, Record ATIS updates, Digital log of all clearances, Printable flight log, Add flight number to log

**Features:** macOS Compatibility

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Clearance Keypad | $0.99 | one-time |
| Qwerty Keypad | $0.99 | one-time |
| Azerty Keypad | $0.99 | one-time |
| CDU Keypad | $0.99 | one-time |
| Qwertz Keypad | $0.99 | one-time |


### Cost Index

[App page](https://appshunter.io/ios/app/cost-index/id671845599)

This app helps airline and corporate aircraft operators achieve significant operational savings by calculating the optimum cruise speed for flights based on pilot-inputted conditions and aircraft-specific data. It offers advanced features for cost, fuel, and time optimization, including level change analysis and turbulence margin adjustments.

**Highlights:** Optimum cruise speed calculation, Customizable operational data display, Minimum fuel burn speed for long range, Turbulence margin adjustment, Level change analysis for climb/descent decisions, Automated data updates

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Readback free?

Readback is free to download, with in-app purchases available.

### Is Cost Index free?

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

### Which has better reviews, Readback or Cost Index?

Cost Index is rated higher. Readback averages 2.3 out of 5 from 8 ratings, while Cost Index averages 5.0 from 1 ratings.

### Do Readback or Cost Index have ads?

Neither Readback nor Cost Index shows ads.

### Which is updated more often, Readback or Cost Index?

Readback ships an update every 6 months, and Cost Index every 16 months. Most recently, Readback was updated on October 3, 2026 and Cost Index on October 6, 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.*