# Interpolation 1.4 vs CX

The clearest difference is price: Interpolation 1.4 at Free against CX's $19.99. Interpolation 1.4 also leads on update cadence (every 3 weeks vs every 8 months) and iOS requirement (9.0 vs 17.2). CX's advantage is rating (3.7 vs 3.5) and chart position (#68 vs unranked). On review sentiment, ratings volume, ads and in-app purchases there is nothing between them.

Interpolation 1.4 is free to download; CX costs $19.99 up front. Neither carries in-app purchases, so what you see is what you pay.

CX holds the better App Store score, 3.7 against 3.5. Both are backed by a comparable volume of ratings — 6 and 11 respectively. Written reviews point the same way: 33% of Interpolation 1.4's written reviews are positive against 36% of CX's.

Interpolation 1.4 ships an update every 3 weeks, CX every 8 months. The most recent releases landed on September 17, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Interpolation 1.4 | CX |
| --- | --- | --- |
| Price | **Free** | $19.99 |
| Rating | [3.5 (6 ratings)](https://appshunter.io/ios/app/interpolation-14/id557950545/reviews) | **[3.7 (11 ratings)](https://appshunter.io/ios/app/cx-3-flight-computer/id1645428895/reviews)** |
| Number of ratings | 6 | **11** |
| Positive reviews | 33.3% of reviews | **35.7% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 8 months |
| Monetization | **Free** | Paid |
| Best chart rank | — | **#68** |
| Size | 1 MB | 3 MB |
| Requires iOS | **9.0** | 17.2 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [ZOFTERM](https://appshunter.io/developer/557950548) | [ASA](https://appshunter.io/developer/334278379) |

## What reviewers say

### Interpolation 1.4

[App page](https://appshunter.io/ios/app/interpolation-14/id557950545)

This utility calculates linear or quadratic interpolations. It provides a straightforward tool for mathematical estimations based on given data points.

**Highlights:** Linear interpolation calculation, Quadratic interpolation calculation, Mathematical estimation tool

**Features:** macOS Compatibility

**In-app purchases:** none


### CX

[App page](https://appshunter.io/ios/app/cx-3-flight-computer/id1645428895)

**Currently charting:** #68 Top Paid · Utilities (US App Store)

This aviation tool simplifies flight planning for pilots. It offers accurate calculations for time, speed, distance, fuel, and more, along with unit conversions and a built-in calculator. Designed for ease of use, it guides users through flight planning and execution with a natural menu flow.

**Highlights:** Flight planning calculations, Time, speed, distance functions, Fuel and altitude calculations, Unit conversions (12 categories), Weight and balance calculations, Holding pattern details, Built-in calculator, clock, timer

**In-app purchases:** none


## Frequently asked questions

### Is Interpolation 1.4 free?

Interpolation 1.4 is free to download, with no in-app purchases.

### Is CX free?

CX costs $19.99, with no in-app purchases.

### Which has better reviews, Interpolation 1.4 or CX?

CX is rated higher. Interpolation 1.4 averages 3.5 out of 5 from 6 ratings, while CX averages 3.7 from 11 ratings.

### Do Interpolation 1.4 or CX have ads?

Neither Interpolation 1.4 nor CX shows ads.

### Which is updated more often, Interpolation 1.4 or CX?

Interpolation 1.4 ships an update every 3 weeks, and CX every 8 months. Most recently, Interpolation 1.4 was updated on September 17, 2026 and CX on October 13, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*