# SensoryStone vs Undulate

The clearest difference is update cadence: Undulate at every 9 days against SensoryStone's monthly. SensoryStone's advantage is device support (3 vs 1). On price, ads, in-app purchases and iOS requirement there is nothing between them.

Both are free to download. SensoryStone sells 1 in-app purchase, starting at $5.99 per year and Undulate sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

SensoryStone ships an update monthly, Undulate every 9 days. The most recent releases landed on October 7, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | SensoryStone | Undulate |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/undulate/id6758805133/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 9 days** |
| Size | 10 MB | 1 MB |
| Requires iOS | **15.5** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [阳 赵](https://appshunter.io/developer/1863829449) | [Abhishek Gawde](https://appshunter.io/developer/1853271112) |

## What reviewers say

### SensoryStone

[App page](https://appshunter.io/ios/app/sensorystone/id6756968561)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium Subscription | $5.99 | per year |


### Undulate

[App page](https://appshunter.io/ios/app/undulate/id6758805133)

**Features:** macOS Compatibility

**In-app purchases (1)**

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


## Frequently asked questions

### Is SensoryStone free?

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

### Is Undulate free?

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

### Do SensoryStone or Undulate have ads?

Neither SensoryStone nor Undulate shows ads.

### Which is updated more often, SensoryStone or Undulate?

SensoryStone ships an update monthly, and Undulate every 9 days. Most recently, SensoryStone was updated on October 7, 2026 and Undulate on October 24, 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.*