# OEI Sim Pro vs ECG Vector

The clearest difference is in-app purchases: OEI Sim Pro at none against ECG Vector's 1. OEI Sim Pro also leads on iOS requirement (14.1 vs 17.0). ECG Vector's advantage is update cadence (every 9 days vs every 23 months) and device support (3 vs 1). On price and ads there is nothing between them.

Both are free to download. ECG Vector sells 1 one-off in-app purchase. OEI Sim Pro asks for nothing beyond the download.

OEI Sim Pro ships an update every 23 months, ECG Vector every 9 days. The most recent releases landed on October 24, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | OEI Sim Pro | ECG Vector |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/oei-sim-pro/id1576212260/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 23 months | **Every 9 days** |
| Size | 112 MB | 12 MB |
| Requires iOS | **14.1** | 17.0 |
| Devices | iPad | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Operative Experience Inc](https://appshunter.io/developer/1309239394) | [Takashi Nakano](https://appshunter.io/developer/6780341829) |

## What reviewers say

### OEI Sim Pro

[App page](https://appshunter.io/ios/app/oei-sim-pro/id1576212260)

**Features:** macOS Compatibility

**In-app purchases:** none


### ECG Vector

[App page](https://appshunter.io/ios/app/ecg-vector/id6798066790)

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| ECG Vector Pro | $6.99 | one-time |


## Frequently asked questions

### Is OEI Sim Pro free?

OEI Sim Pro is free to download, with no in-app purchases.

### Is ECG Vector free?

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

### Do OEI Sim Pro or ECG Vector have ads?

Neither OEI Sim Pro nor ECG Vector shows ads.

### Which is updated more often, OEI Sim Pro or ECG Vector?

OEI Sim Pro ships an update every 23 months, and ECG Vector every 9 days. Most recently, OEI Sim Pro was updated on October 24, 2026 and ECG Vector on October 14, 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.*