# Directional Survey Methods vs ECD Calculator

The clearest difference is in-app purchases: Directional Survey Methods at none against ECD Calculator's 2. Directional Survey Methods also leads on iOS requirement (12.0 vs 15.1). ECD Calculator's advantage is update cadence (every 5 days vs every 50 months). On price, ads and device support there is nothing between them.

Both are free to download. ECD Calculator sells 2 one-off in-app purchases. Directional Survey Methods asks for nothing beyond the download.

Directional Survey Methods ships an update every 50 months, ECD Calculator every 5 days. The most recent releases landed on October 1, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | Directional Survey Methods | ECD Calculator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (5 ratings)](https://appshunter.io/ios/app/ecd-calculator/id6754762850/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 50 months | **Every 5 days** |
| Monetization | — | Free |
| Size | 7 MB | 45 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Carlos Moura](https://appshunter.io/developer/407501202) | [Drillsoft LLC](https://appshunter.io/developer/1787962403) |

## What reviewers say

### Directional Survey Methods

[App page](https://appshunter.io/ios/app/directional-survey-methods/id1130800392)

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

**In-app purchases:** none


### ECD Calculator

[App page](https://appshunter.io/ios/app/ecd-calculator/id6754762850)

This utility app assists drilling and mud engineers in calculating Equivalent Circulating Density (ECD) at any point during operations. It offers a streamlined process with just a few clicks.

**Highlights:** ECD calculation, Drilling engineering, Mud engineering, Point-of-operation calculation, Streamlined interface

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 50 credits | $3.99 | one-time |
| 300 Credits | $9.99 | one-time |


## Frequently asked questions

### Is Directional Survey Methods free?

Directional Survey Methods is free to download, with no in-app purchases.

### Is ECD Calculator free?

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

### Do Directional Survey Methods or ECD Calculator have ads?

Neither Directional Survey Methods nor ECD Calculator shows ads.

### Which is updated more often, Directional Survey Methods or ECD Calculator?

Directional Survey Methods ships an update every 50 months, and ECD Calculator every 5 days. Most recently, Directional Survey Methods was updated on October 1, 2026 and ECD Calculator on October 6, 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.*