# Differential Pressure vs MachBackflow

The clearest difference is in-app purchases: Differential Pressure at none against MachBackflow's 3. Differential Pressure also leads on device support (3 vs 1) and iOS requirement (12.0 vs 16.6). MachBackflow's advantage is update cadence (every 2 months vs every 4 months). On price and ads there is nothing between them.

Both are free to download. MachBackflow sells 3 one-off in-app purchases. Differential Pressure asks for nothing beyond the download.

Differential Pressure ships an update every 4 months, MachBackflow every 2 months. The most recent releases landed on October 26, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | Differential Pressure | MachBackflow |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (2 ratings)](https://appshunter.io/ios/app/machbackflow/id6448785820/reviews)** |
| Number of ratings | — | **2** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 months** |
| Monetization | — | Free with in-app purchases |
| Size | 4 MB | 18 MB |
| Requires iOS | **12.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Kane Asia Inc.](https://appshunter.io/developer/1542732944) | [WTM Solutions, LLC](https://appshunter.io/developer/1673242880) |

## What reviewers say

### Differential Pressure

[App page](https://appshunter.io/ios/app/differential-pressure/id1099444569)

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

**In-app purchases:** none


### MachBackflow

[App page](https://appshunter.io/ios/app/machbackflow/id6448785820)

This app streamlines backflow prevention assembly testing by capturing real-time pressure readings or allowing manual entry. It automatically generates accurate reports and manages all your tests efficiently from the field.

**Highlights:** Real-time pressure capture, Supports all assembly types and procedures, Autofill property and assembly information, Accurate, error-free PDF reports, Cloud synchronization, Powerful search and filters

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Credits 10 | $24.99 | one-time |
| Credits 100 | $174.99 | one-time |
| Credits 250 | $299.99 | one-time |


## Frequently asked questions

### Is Differential Pressure free?

Differential Pressure is free to download, with no in-app purchases.

### Is MachBackflow free?

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

### Do Differential Pressure or MachBackflow have ads?

Neither Differential Pressure nor MachBackflow shows ads.

### Which is updated more often, Differential Pressure or MachBackflow?

Differential Pressure ships an update every 4 months, and MachBackflow every 2 months. Most recently, Differential Pressure was updated on October 26, 2026 and MachBackflow on September 18, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*