# DifCal vs 少年卫星跟踪台

The clearest difference is in-app purchases: DifCal at none against 少年卫星跟踪台's 2. DifCal also leads on ads (none vs shown) and iOS requirement (12.0 vs 16.0). 少年卫星跟踪台's advantage is update cadence (every 4 days vs every 15 months). On price and device support there is nothing between them.

Both are free to download. 少年卫星跟踪台 sells 2 one-off in-app purchases. DifCal asks for nothing beyond the download.

DifCal ships an update every 15 months, 少年卫星跟踪台 every 4 days. The most recent releases landed on November 1, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | DifCal | 少年卫星跟踪台 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 15 months | **Every 4 days** |
| Size | 9 MB | 10 MB |
| Requires iOS | **12.0** | 16.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Sean Brennan](https://appshunter.io/developer/898026482) | [峰 于](https://appshunter.io/developer/6772845425) |

## What reviewers say

### DifCal

[App page](https://appshunter.io/ios/app/difcal/id898026479)

**Features:** Vision Pro support

**In-app purchases:** none


### 少年卫星跟踪台

[App page](https://appshunter.io/ios/app/id6796221077)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Ad-free Base | Free | one-time |
| Pro Device Control | $9.90 | one-time |


## Frequently asked questions

### Is DifCal free?

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

### Is 少年卫星跟踪台 free?

少年卫星跟踪台 is free to download, with in-app purchases available.

### Do DifCal or 少年卫星跟踪台 have ads?

少年卫星跟踪台 shows ads; DifCal does not.

### Which is updated more often, DifCal or 少年卫星跟踪台?

DifCal ships an update every 15 months, and 少年卫星跟踪台 every 4 days. Most recently, DifCal was updated on November 1, 2026 and 少年卫星跟踪台 on October 31, 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.*