# SURF vs SPIRO

The clearest difference is review sentiment: SURF at 67% against SPIRO's 0%. SURF also leads on price (Free vs $3.99). SPIRO's advantage is in-app purchases (none vs 1) and iOS requirement (12.0 vs 16.0). On update cadence, ads and device support there is nothing between them.

SURF is free to download; SPIRO costs $3.99 up front. SURF sells 1 in-app purchase, starting at $99.99 per year. SPIRO asks for nothing beyond the download.

SURF ships an update every 5 months, SPIRO every 7 months. The most recent releases landed on September 22, 2026 and July 9, 2026 respectively.

## The numbers

| Metric | SURF | SPIRO |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Positive reviews | **66.7% of reviews** | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 5 months** | Every 7 months |
| Monetization | Subscription | **Paid** |
| Size | 204 MB | 125 MB |
| Requires iOS | 16.0 | **12.0** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 17+ | 12+ |
| Developer | [Philippe FURGER](https://appshunter.io/developer/1055742280) | [Universite Laval](https://appshunter.io/developer/386592978) |

## What reviewers say

### SURF

[App page](https://appshunter.io/ios/app/surf/id1055743301)

Access evidence-based medical content for internal medicine, differential diagnosis, and lab values. This comprehensive guide is designed for residents, general practitioners, and specialists, offering a vast amount of information from multiple expert-authored books.

**Highlights:** Evidence-based medical content, Differential diagnosis of symptoms, Lab value interpretation, Comprehensive internal medicine, Links to external calculators, Accessible on multiple devices

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 year | $99.99 | per year |


### SPIRO

[App page](https://appshunter.io/ios/app/spiro/id1135982423)

This medical app assists healthcare professionals and students in interpreting spirometry tests. It provides diagnostic and treatment suggestions based on entered data and offers access to educational materials and respiratory health guidelines.

**Highlights:** Interpret spirometry tests, Diagnostic suggestions, Treatment suggestions, Access respiratory guidelines, Educational material, Patient follow-up tool

**In-app purchases:** none


## Frequently asked questions

### Is SURF free?

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

### Is SPIRO free?

SPIRO costs $3.99, with no in-app purchases.

### Do SURF or SPIRO have ads?

Neither SURF nor SPIRO shows ads.

### Which is updated more often, SURF or SPIRO?

SURF ships an update every 5 months, and SPIRO every 7 months. Most recently, SURF was updated on September 22, 2026 and SPIRO on July 9, 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.*