# Si vs D

The clearest difference is update cadence: D at every 3 weeks against Si's every 2 months. Si's advantage is iOS requirement (12.4 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Si ships an update every 2 months, D every 3 weeks. The most recent releases landed on June 2, 2026 and September 24, 2026 respectively.

## The numbers

| Metric | Si | D |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/si-manifold/id1294563130/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 3 weeks** |
| Monetization | Free | — |
| Size | 87 MB | 24 MB |
| Requires iOS | **12.4** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [SAUERMANN INDUSTRIE](https://appshunter.io/developer/1169513729) | [davide Sbreviglieri](https://appshunter.io/developer/562172174) |

## What reviewers say

### Si

[App page](https://appshunter.io/ios/app/si-manifold/id1294563130)

Instantly and accurately displays numerous measurements like pressure and temperature for specific devices. It supports long-range Bluetooth connectivity and can store and update approximately 120 refrigerants, including environmentally friendly options.

**Highlights:** Real-time measurement display, Bluetooth 4.2 connectivity (up to 30m), Storage for ~120 refrigerants, Environmentally friendly refrigerant support, Updateable refrigerant database

**In-app purchases:** none


### D

[App page](https://appshunter.io/ios/app/d-tec/id1509408218)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Si free?

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

### Is D free?

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

### Do Si or D have ads?

Neither Si nor D shows ads.

### Which is updated more often, Si or D?

Si ships an update every 2 months, and D every 3 weeks. Most recently, Si was updated on June 2, 2026 and D on September 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.*