# Principia vs Sing Songo

The clearest difference is update cadence: Principia at every 3 weeks against Sing Songo's every 2 months. On price, ads, in-app purchases and device support there is nothing between them.

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

Principia ships an update every 3 weeks, Sing Songo every 2 months. The most recent releases landed on October 27, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | Principia | Sing Songo |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 2 months |
| Size | 46 MB | 60 MB |
| Requires iOS | **12.0** | 13.0 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Abdul Rafeeque Parakkal](https://appshunter.io/developer/1464562964) | [Musiko Musika](https://appshunter.io/developer/1555056776) |

## What reviewers say

### Principia

[App page](https://appshunter.io/ios/app/principia-the-learning-app/id1540900536)

**Features:** macOS Compatibility

**In-app purchases:** none


### Sing Songo

[App page](https://appshunter.io/ios/app/sing-songo/id1555056774)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Principia free?

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

### Is Sing Songo free?

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

### Do Principia or Sing Songo have ads?

Neither Principia nor Sing Songo shows ads.

### Which is updated more often, Principia or Sing Songo?

Principia ships an update every 3 weeks, and Sing Songo every 2 months. Most recently, Principia was updated on October 27, 2026 and Sing Songo 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.*