# Heightometer vs Flexx

The clearest difference is price: Flexx at Free against Heightometer's $0.99. Heightometer's advantage is in-app purchases (none vs 2) and iOS requirement (9.0 vs 15.6). On update cadence, ads and device support there is nothing between them.

Flexx is free to download; Heightometer costs $0.99 up front. Flexx sells 2 in-app purchases, starting at $9.99 per month. Heightometer asks for nothing beyond the download.

Both ship on a similar rhythm, roughly every 2 days. The most recent releases landed on October 30, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Heightometer | Flexx |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | **[3.0 (4 ratings)](https://appshunter.io/ios/app/heightometer-height-predictor/id1620546792/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 days | Every 2 days |
| Monetization | Paid | — |
| Size | 43 MB | 79 MB |
| Requires iOS | **9.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Kartik Khatana](https://appshunter.io/developer/1664325011) | [Ankit Priyadarshi](https://appshunter.io/developer/1824085646) |

## What reviewers say

### Heightometer

[App page](https://appshunter.io/ios/app/heightometer-height-predictor/id1620546792)

This application uses scientific and mathematical calculations based on a child's growth rate to predict their approximate future height. It provides future height estimates in both inches and centimeters for children aged 8 to 18.

**Highlights:** Future height prediction, Growth rate analysis, Scientific calculations, Mathematical formulas, Height in inches and centimeters, Child age range 8-18

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

**In-app purchases:** none


### Flexx

[App page](https://appshunter.io/ios/app/flexx-workout-planner/id6751598622)

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $9.99 | per month |
| Yearly Subscription | $29.99 | per year |


## Frequently asked questions

### Is Heightometer free?

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

### Is Flexx free?

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

### Do Heightometer or Flexx have ads?

Neither Heightometer nor Flexx shows ads.

### Which is updated more often, Heightometer or Flexx?

Heightometer ships an update every 2 days, and Flexx every 2 days. Most recently, Heightometer was updated on October 30, 2026 and Flexx on October 25, 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.*