The iOS sideloading ecosystem has grown from a handful of niche tools to a collection of mature, feature-rich platforms. If you're getting into sideloading for the first time, the number of options can be overwhelming. AltStore, Feather, ESign, Scarlet, FlareStore. What do they all do, and which one should you use? This guide compares the major tools so you can pick the right workflow for your needs.
AltStore
AltStore is one of the oldest and most well-known sideloading tools. Created by Riley Testut (the developer behind the Delta emulator), AltStore was originally designed as a way to sideload apps using a free Apple Developer account.
How it works: AltStore requires a companion app (AltServer) running on a Mac or Windows PC on the same Wi-Fi network as your device. AltServer communicates with Apple's servers using your Apple ID to sign and install apps. Your computer handles the signing, and the apps are pushed to your device over the network.
Strengths: Well-established, large community, trusted developer, supports app sources/repositories, automatic refresh of apps before they expire.
Limitations: Requires a computer running AltServer on the same network. Free accounts are limited to 3 sideloaded apps with 7-day expirations. Must refresh apps within 7 days or they stop working. Can be finicky with network connectivity.
Best for: Users who have a Mac/PC that's regularly on the same network as their iPhone and don't mind the 3-app limit.
Feather
Feather is an on-device signing and installation tool. Unlike AltStore, Feather runs entirely on your iPhone or iPad, no computer needed. It's become one of the most popular sideloading tools due to its convenience and feature set.
How it works: You provide Feather with a signing certificate (P12 + provisioning profile), and it handles signing and installing apps directly on your device. It supports app repositories for browsing available apps, and can import IPA files from the Files app or URLs.
Strengths: No computer required, clean interface, repository support, certificate management, on-device signing, actively maintained.
Limitations: Feather itself needs to be sideloaded first (chicken-and-egg problem: you need another tool to install Feather initially). Requires a paid or enterprise certificate for the best experience.
Best for: Users who want an all-in-one on-device solution and have a signing certificate. FlareStore's App Installer can help you get Feather installed initially.
ESign
ESign is a Chinese-developed on-device signing tool with a long history in the sideloading community. It's feature-rich and supports advanced signing options that other tools don't offer.
How it works: Similar to Feather. You install ESign on your device, provide a certificate, and it handles signing and installation. ESign also supports importing certificates directly and has built-in repository browsing.
Strengths: Extensive feature set, supports many certificate formats, powerful advanced options, large repository ecosystem (particularly popular in Asian markets).
Limitations: Interface is less polished than Feather, some UI elements are poorly translated, updates can be inconsistent, also needs to be sideloaded initially.
Best for: Power users who want maximum control over the signing process and don't mind a less refined interface.
FlareStore
FlareStore is a full platform for sideloading that works on every Apple device. It has a web-based signer that runs in any browser with no PC required, plus native apps for iPhone, iPad, Mac, Apple TV, Apple Watch, and Vision Pro. Beyond just signing, FlareStore provides a complete suite of tools: certificate sales, UDID grabbing, DNS anti-revoke, repository creation and decoding, app installation, and more.
How it works: Visit flarestore.app/signer/, upload your IPA file and signing certificate, and the Web Signer signs the app on FlareStore's servers. You then install the signed app via OTA (over-the-air) directly from the browser. FlareStore also sells paid certificates at flarestore.vip, offers a UDID grabber, DNS anti-revoke profiles, and repository tools.
Strengths: No app to install first (works in any browser), no computer needed, comprehensive tool suite beyond just signing, certificate store with multiple tiers and individual UDID registration, free DNS anti-revoke, works on every platform (iPhone, iPad, Mac, Apple TV, Vision Pro).
Limitations: Requires uploading your certificate to FlareStore's servers for signing (some users prefer local signing). No on-device app management like Feather offers (though the FlareStore App adds this).
Best for: Users who want a simple browser-based workflow, first-time sideloaders, anyone who needs reliable certificates and signing in one place, Apple TV and Vision Pro users.
Combining Tools
Most experienced sideloaders use multiple tools together. A common setup:
- FlareStore for purchasing a reliable paid certificate at flarestore.vip, grabbing your UDID, and initial signing
- Feather (installed via FlareStore's App Installer) for ongoing on-device app management
- FlareStore DNS profile from flarestore.app/dns/ for an extra layer of revocation protection
This gives you the reliability of FlareStore's paid certificates, the convenience of web-based tools for setup, plus Feather's on-device signing for day-to-day use. Avoid relying on free certificates in any workflow. They'll break your setup unpredictably.
| Feature | AltStore | Feather | ESign | FlareStore |
|---|---|---|---|---|
| Computer required | Yes | No | No | No |
| Signing location | Computer | On-device | On-device | Server-side |
| Repository support | Yes | Yes | Yes | Yes (tools) |
| Certificate included | No (uses Apple ID) | No | No | Yes (store) |
| Free option | Yes (3 apps, 7-day) | Yes (BYOC) | Yes (BYOC) | Paid recommended |
| Apple TV support | No | No | No | Yes |
| Vision Pro support | No | Partial | No | Yes |
| Browser-based | No | No | No | Yes |
The Bottom Line
There's no single "best" tool. It depends on your situation. If you're just getting started, FlareStore's web-based approach has the lowest barrier to entry and the easiest path to getting a reliable paid certificate. If you want an on-device app manager after your initial setup, install Feather. If you have a computer always available, AltStore is a solid option with its free Apple ID signing (though limited to 3 apps with 7-day expiration). And if you want maximum power and customization, ESign has the most features.
Whichever tool you choose, the most important factor for a smooth sideloading experience is a reliable certificate. Purchase one from flarestore.vip. It makes every tool work better.