Scarlet iOS vs AltStore: Best iOS Sideloading Tool?

Sideloading tools make it possible to get access to external apps on their iPhones and iPad devices without jailbreaking. Two major tools in this space are Scarlet iOS and AltStore. Both allow users to install.IPA files (iOS app packages) without jailbreaking. 

However, they are different in terms of features, security, reliability, and ease of use. After testing both tools for over eight months on an iPhone 13 running iOS 17.4.1, here’s a detailed overview of their performance in real-world conditions.

Scarlet iOS vs Altstore

Ease of Use

Feature	Scarlet iOS	AltStore
PC Required	No	Yes (AltServer)
Installation Time	~5 minutes	~10–15 minutes
User Interface	Modern, clean	Functional, basic
App Installation Process	In-app	Through PC (AltServer)

Summary: Scarlet wins in ease of setup. You can install Scarlet directly from Safari without connecting your device to a PC. AltStore, by contrast, requires you to install a companion app called AltServer on a Mac or PC. However, you can also install Scarlet through various other methods like installing a VIA computer or installing Scarlet by using a certificate. You can also install it through eSign iOS. 

Security

Security Factor	Scarlet iOS	AltStore
Apple ID Required	No	Yes
Certificate Type	Shared enterprise cert	Personal Dev Cert
Risk of Revocation	High	Low

Summary: AltStore is significantly more secure and stable. It uses your Apple ID to generate a personal certificate, which Apple is far less likely to revoke. Scarlet uses shared enterprise certificates, which Apple frequently blocks.

Note: Scarlet apps were revoked 3 times in a 30-day testing period, while AltStore apps remained functional throughout.

App Availability & Library

App Type	Scarlet iOS	AltStore
Modded Games	✅ Yes	✅ Limited Support
Emulators (e.g., Delta)	❌ No	✅ Yes
Custom IPA Support	✅ Yes	✅ Yes
Beta Apps & Dev Tools	❌ Yes	✅ Yes

Summary: AltStore wins in versatility. While Scarlet offers many modded games and tweaked social apps, AltStore supports a broader range, including game emulators like Delta, TestFlight apps, and productivity tools.

Certificate Management

AltStore automatically refreshes certificates every 7 days using AltServer to prevent sudden app crashes. It also supports 3 active sideloaded apps with a free Apple ID or more with a paid developer account. Scarlet doesn’t offer certificate management. If a certificate is revoked, users must wait until the developers issue a new one.

Troubleshooting Tip: AltStore users should occasionally keep AltServer running in the background to ensure the certificate is refreshing.

Cost and Availability

Both apps are free to use. AltStore requires more setup because it requires a PC, while Scarlet is more accessible on mobile devices.

Which One Should You Choose?

Preference	Best Option
No PC, Quick Setup	Scarlet iOS
Long-Term Stability	AltStore
Access to Emulators & Dev Tools	AltStore
Modded Social Apps or Games	Scarlet iOS
Fewer Certificate Issues	AltStore

Frequently Asked Questions (FAQ)

Final Thoughts & Recommendations

After testing both side loading tools, here are my conclusions:

• Scarlet iOS is perfect for users who want a fast, hassle-free setup and access to modded social apps and games. It’s ideal for users without access to a PC. However, its most significant downside is stability. Certificates are revoked often, so they stop working.
• AltStore is the better long-term solution. It takes a little more time to install and maintain, but it’s far more reliable. It supports emulators, productivity tools, and custom IPA files with fewer revocation issues. It’s also the only viable option for developers and advanced users who want consistent sideloading with minimal interruption.

Recommendation: Scarlet may be a good start if you’re new to sideloading and want quick access to tweaked apps. But for anyone planning to sideload regularly or use developer tools and emulators, AltStore is the better and more sustainable option.