# Advanced Dual N vs Echo

The clearest difference is device support: Advanced Dual N at 3 against Echo's 1. On price, ads, in-app purchases and iOS requirement there is nothing between them.

Both are free to download. Advanced Dual N sells 1 one-off in-app purchase and Echo sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

## The numbers

| Metric | Advanced Dual N | Echo |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | — |
| Size | 41 MB | 10 MB |
| Requires iOS | **15.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Gustavo cesar Sola Barreto Marcelino](https://appshunter.io/developer/1875104005) | [AprilNEA LLC](https://appshunter.io/developer/1823519141) |

## What reviewers say

### Advanced Dual N

[App page](https://appshunter.io/ios/app/advanced-dual-n-back/id6758858941)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Unlock | $3.99 | one-time |


### Echo

[App page](https://appshunter.io/ios/app/echo-n-back-math/id6783219758)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Echo Pro | $4.99 | one-time |


## Frequently asked questions

### Is Advanced Dual N free?

Advanced Dual N is free to download, with in-app purchases available.

### Is Echo free?

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

### Do Advanced Dual N or Echo have ads?

Neither Advanced Dual N nor Echo shows ads.

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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.*