# SDT VR (Google Cardboard) vs Flash PDF

The clearest difference is ads: SDT VR (Google Cardboard) at none against Flash PDF's shown. SDT VR (Google Cardboard) also leads on monetization model (free vs ad-supported) and iOS requirement (8.0 vs 15.0). On price, update cadence, 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.

SDT VR (Google Cardboard) ships an update every 3 weeks, Flash PDF fortnightly. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | SDT VR (Google Cardboard) | Flash PDF |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/flash-pdffast-readscan/id6742016312/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 3 weeks | **Fortnightly** |
| Monetization | **Free** | Ad-supported |
| Size | 248 MB | 29 MB |
| Requires iOS | **8.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [SDT International SA](https://appshunter.io/developer/1275552047) | [VISION NETWORK TECHNOLOGY CO.,LIMITED](https://appshunter.io/developer/1717534539) |

## What reviewers say

### SDT VR (Google Cardboard)

[App page](https://appshunter.io/ios/app/sdt-vr-google-cardboard/id1414322113)

Explore the capabilities of the SDT340 Ultrasound Solution. This application demonstrates how to predict failures, manage energy expenses, and enhance product quality for improved asset uptime.

**Highlights:** Predict equipment failures, Control energy costs, Improve product quality, Enhance asset uptime, Demonstrates SDT340 Ultrasound Solution

**Features:** macOS Compatibility

**In-app purchases:** none


### Flash PDF

[App page](https://appshunter.io/ios/app/flash-pdffast-readscan/id6742016312)

Easily convert photos and images into PDF documents. Merge multiple PDFs into one or split large files into smaller ones. Streamline your document processing with a simple and intuitive interface.

**Highlights:** Photo to PDF conversion, Image to PDF conversion, Merge PDF files, Split PDF files, Intuitive interface

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is SDT VR (Google Cardboard) free?

SDT VR (Google Cardboard) is free to download, with no in-app purchases.

### Is Flash PDF free?

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

### Do SDT VR (Google Cardboard) or Flash PDF have ads?

Flash PDF shows ads; SDT VR (Google Cardboard) does not.

### Which is updated more often, SDT VR (Google Cardboard) or Flash PDF?

SDT VR (Google Cardboard) ships an update every 3 weeks, and Flash PDF fortnightly. Most recently, SDT VR (Google Cardboard) was updated on October 24, 2026 and Flash PDF on October 25, 2026.

---

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