# KM eFlash vs WattCheck

The clearest difference is in-app purchases: KM eFlash at none against WattCheck's 3. KM eFlash also leads on update cadence (every 3 days vs every 5 weeks) and iOS requirement (16.4 vs 18.0). On price, ads and device support there is nothing between them.

Both are free to download. WattCheck sells 3 in-app purchases, starting at $1.99 per 7 days. KM eFlash asks for nothing beyond the download.

KM eFlash ships an update every 3 days, WattCheck every 5 weeks. The most recent releases landed on October 17, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | KM eFlash | WattCheck |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[1.0 (1 ratings)](https://appshunter.io/ios/app/wattcheck-cable-tester/id6790480866/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 3 days** | Every 5 weeks |
| Monetization | — | Freemium |
| Size | 52 MB | 16 MB |
| Requires iOS | **16.4** | 18.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [KM Engineers GmbH](https://appshunter.io/developer/1799146204) | [SUN TEAME PTE. LTD.](https://appshunter.io/developer/941073095) |

## What reviewers say

### KM eFlash

[App page](https://appshunter.io/ios/app/km-eflash/id6742645180)

**Features:** macOS Compatibility

**In-app purchases:** none


### WattCheck

[App page](https://appshunter.io/ios/app/wattcheck-cable-tester/id6790480866)

This app helps you test and compare your charging cables and power adapters. It estimates charging performance over time, allowing you to rank your cables and identify the best and weakest charging gear. Clean up your cable drawer and stop guessing which cable is slowing you down.

**Highlights:** Charging performance test, 5, 10, and 20 minute results, Cable ranking, Best and weakest cable detection, Charger comparison, Test history, CSV export

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| WattCheck Premium Weekly | $1.99 | per 7 days |
| WattCheck Premium Monthly | $5.99 | per month |
| WattCheck Premium Yearly | $29.99 | per year |


## Frequently asked questions

### Is KM eFlash free?

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

### Is WattCheck free?

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

### Do KM eFlash or WattCheck have ads?

Neither KM eFlash nor WattCheck shows ads.

### Which is updated more often, KM eFlash or WattCheck?

KM eFlash ships an update every 3 days, and WattCheck every 5 weeks. Most recently, KM eFlash was updated on October 17, 2026 and WattCheck on October 7, 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.*