# e85Cal vs RENNtech HSM

The clearest difference is iOS requirement: e85Cal at 12.1 against RENNtech HSM's 16.0. On price, update cadence, ads and in-app purchases there is nothing between them.

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

e85Cal ships an update every 4 months, RENNtech HSM every 3 months. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | e85Cal | RENNtech HSM |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (37 ratings)](https://appshunter.io/ios/app/e85cal/id1470313135/reviews)** | — |
| Number of ratings | **37** | — |
| Positive reviews | 83.3% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 months** |
| Monetization | Free | — |
| Size | 15 MB | 4 MB |
| Requires iOS | **12.1** | 16.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Michael Joe](https://appshunter.io/developer/1132486512) | [Dian Esterhuyse](https://appshunter.io/developer/1715552648) |

## What reviewers say

### e85Cal

[App page](https://appshunter.io/ios/app/e85cal/id1470313135)

This app assists users in calculating the precise amounts of standard and ethanol gasoline needed to achieve a desired ethanol percentage in their fuel mix. It simplifies the process by taking into account tank size, current fuel level, and the ethanol content of available fuel types.

**Highlights:** Calculate ethanol percentage goal, Enter gas tank size, Input standard pump gas ethanol %, Input ethanol pump gas ethanol %, Set target ethanol % mix, Enter current fuel level %

**Features:** macOS Compatibility

**In-app purchases:** none


### RENNtech HSM

[App page](https://appshunter.io/ios/app/renntech-hsm/id6471528927)

**In-app purchases:** none


## Frequently asked questions

### Is e85Cal free?

e85Cal is free to download, with no in-app purchases.

### Is RENNtech HSM free?

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

### Do e85Cal or RENNtech HSM have ads?

Neither e85Cal nor RENNtech HSM shows ads.

### Which is updated more often, e85Cal or RENNtech HSM?

e85Cal ships an update every 4 months, and RENNtech HSM every 3 months. Most recently, e85Cal was updated on October 24, 2026 and RENNtech HSM on October 25, 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.*