# Co vs Protractor Teacher

The clearest difference is device support: Protractor Teacher at 3 against Co's 1. Protractor Teacher also leads on price ($0.99 vs $1.99). On update cadence, ads, in-app purchases and iOS requirement there is nothing between them.

Co costs $1.99 and Protractor Teacher $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Co ships an update every 30 months, Protractor Teacher every 42 months. The most recent releases landed on October 10, 2026 and October 13, 2026 respectively.

## The numbers

| Metric | Co | Protractor Teacher |
| --- | --- | --- |
| Price | $1.99 | **$0.99** |
| Rating | — | **[4.5 (2 ratings)](https://appshunter.io/ios/app/protractor-teacher/id1526985063/reviews)** |
| Number of ratings | — | **2** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 30 months** | Every 42 months |
| Monetization | — | Paid |
| Size | 17 MB | 1 MB |
| Requires iOS | **12.0** | 13.0 |
| Devices | iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Aleesha Kondys](https://appshunter.io/developer/478569400) | [Alistair Shaw](https://appshunter.io/developer/959356999) |

## What reviewers say

### Co

[App page](https://appshunter.io/ios/app/co-ordinates/id594462845)

**Features:** macOS Compatibility

**In-app purchases:** none


### Protractor Teacher

[App page](https://appshunter.io/ios/app/protractor-teacher/id1526985063)

This geometry app overlays a virtual protractor onto images. Users can rotate and move the protractor to learn how to accurately measure angles in various contexts.

**Highlights:** Virtual protractor overlay, Image angle measurement, Protractor rotation, Protractor repositioning, Geometry education tool

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

**In-app purchases:** none


## Frequently asked questions

### Is Co free?

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

### Is Protractor Teacher free?

Protractor Teacher costs $0.99, with no in-app purchases.

### Do Co or Protractor Teacher have ads?

Neither Co nor Protractor Teacher shows ads.

### Which is updated more often, Co or Protractor Teacher?

Co ships an update every 30 months, and Protractor Teacher every 42 months. Most recently, Co was updated on October 10, 2026 and Protractor Teacher on October 13, 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.*