# Sub Buddy vs Learn XML

The clearest difference is price: Learn XML at Free against Sub Buddy's $5.99. Learn XML also leads on update cadence (every 4 months vs every 12 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Learn XML is free to download; Sub Buddy costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Sub Buddy ships an update every 12 months, Learn XML every 4 months. Both last shipped on November 3, 2026.

## The numbers

| Metric | Sub Buddy | Learn XML |
| --- | --- | --- |
| Price | $5.99 | **Free** |
| Rating | **[5.0 (10 ratings)](https://appshunter.io/ios/app/sub-buddy/id1470196349/reviews)** | — |
| Number of ratings | **10** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 12 months | **Every 4 months** |
| Monetization | Paid | — |
| Size | 1.2 GB | 28 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Zoe Summers](https://appshunter.io/developer/1468119556) | [OnePercent](https://appshunter.io/developer/1536020418) |

## What reviewers say

### Sub Buddy

[App page](https://appshunter.io/ios/app/sub-buddy/id1470196349)

This app provides a realistic digital replica of a German U-boat Attack Disc, functioning as a circular slide rule for complex torpedo calculations in WW2 submarine games. It includes 27 training videos and a visual Angle on Bow helper, with customizable controls for left and right-handed users.

**Highlights:** Realistic U-boat Attack Disc simulation, Circular slide rule for torpedo solutions, 27 bundled training videos, Visual Angle on Bow helper, Adjustable time of day and weather, Left and right-handed modes, Customizable menu system

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

**In-app purchases:** none


### Learn XML

[App page](https://appshunter.io/ios/app/learn-xml-onepercent/id1561356815)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Sub Buddy free?

Sub Buddy costs $5.99, with no in-app purchases.

### Is Learn XML free?

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

### Do Sub Buddy or Learn XML have ads?

Neither Sub Buddy nor Learn XML shows ads.

### Which is updated more often, Sub Buddy or Learn XML?

Sub Buddy ships an update every 12 months, and Learn XML every 4 months. Most recently, Sub Buddy was updated on November 3, 2026 and Learn XML on November 3, 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.*