# Oilcalcs vs Substations

The clearest difference is price: Substations at Free against Oilcalcs's $9.99. Substations also leads on iOS requirement (11.0 vs 15.6). Oilcalcs's advantage is update cadence (every 4 months vs every 66 months). On ads, in-app purchases and device support there is nothing between them.

Substations is free to download; Oilcalcs costs $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Oilcalcs ships an update every 4 months, Substations every 66 months. The most recent releases landed on October 4, 2026 and October 11, 2026 respectively.

## The numbers

| Metric | Oilcalcs | Substations |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| Rating | **[4.8 (46 ratings)](https://appshunter.io/ios/app/oilcalcs/id612283154/reviews)** | — |
| Number of ratings | **46** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 66 months |
| Monetization | Paid | — |
| Size | 2 MB | 32 MB |
| Requires iOS | 15.6 | **11.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 12+ |
| Developer | [ron mooring](https://appshunter.io/developer/612283157) | [Delta Sama Jaya Sdn Bhd](https://appshunter.io/developer/1502506485) |

## What reviewers say

### Oilcalcs

[App page](https://appshunter.io/ios/app/oilcalcs/id612283154)

This app provides comprehensive calculations for professionals in the oil and gas industry. It offers versatile tools for volume and weight conversions, density corrections, and blending calculations, supporting various industry tables and units.

**Highlights:** Volume and weight conversions, Density correction for special applications, Viscosity, pour point, and flash point blender, LNG and LPG density calculators, Support for ASTM tables and units, Data export to database

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

**In-app purchases:** none


### Substations

[App page](https://appshunter.io/ios/app/substations/id1502506486)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Oilcalcs free?

Oilcalcs costs $9.99, with no in-app purchases.

### Is Substations free?

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

### Do Oilcalcs or Substations have ads?

Neither Oilcalcs nor Substations shows ads.

### Which is updated more often, Oilcalcs or Substations?

Oilcalcs ships an update every 4 months, and Substations every 66 months. Most recently, Oilcalcs was updated on October 4, 2026 and Substations on October 11, 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.*