AltStore Sideloading Guide — Install Emulators Not on the App Store on iPhone 2026

What you need: iPhone or iPad (iOS 14+), a PC (Windows 10/11) or Mac (macOS 12+), a USB cable, and a free Apple ID.

Step 1 — Install AltServer on your computer

1. Download AltServer from altstore.io (the official site). It is free.
2. On Windows: install and run AltServer. It appears in the system tray.
3. On Mac: install and run AltServer. It appears in the menu bar. Also install Apple Devices (formerly iTunes for Windows / Apple Mobile Device Support) if prompted — AltServer needs it to recognize your iPhone.

Step 2 — Connect your iPhone and install AltStore

1. Connect your iPhone to the computer via USB. Trust the device if prompted on iPhone.
2. On Windows: click the AltServer icon in the system tray → Install AltStore → select your iPhone.
3. On Mac: click the AltServer menu bar icon → Install AltStore → select your iPhone.
4. Enter your Apple ID email and password when prompted. This is used only to sign the app — AltServer does not store it beyond the session. Using a secondary Apple ID is an option but not required.
5. AltStore appears on your iPhone's home screen in about 30 seconds.

Step 3 — Trust the certificate on iPhone

1. On iPhone: Settings → General → VPN & Device Management → tap your Apple ID → Trust.
2. Open AltStore — it should launch without an "Untrusted Developer" error.

Step 4 — Keep AltStore active (refresh every 7 days)

Apple's free developer certificates expire after 7 days. AltStore refreshes automatically when your iPhone is on the same Wi-Fi network as AltServer — no action needed as long as AltServer is running and the app is opened occasionally. If a certificate expires, reinstall the app from AltStore (settings and saves are kept).

EU users (iOS 17.4+ in the European Union): no PC required

Apple's compliance with the EU Digital Markets Act (DMA) allows alternative app marketplaces in the EU. AltStore is an approved EU marketplace, meaning EU users can install AltStore directly from altstore.io in Safari — no AltServer, no PC, no 7-day limit.

1. On your iPhone (EU region, iOS 17.4+): visit altstore.io in Safari and tap Get AltStore.
2. Follow the prompts to add AltStore as a marketplace. iOS shows a system confirmation dialog — tap Allow.
3. AltStore installs and the certificate is managed by Apple's marketplace system (no 7-day expiry).

This path also enables JIT automatically for emulators that need it — a major advantage over the AltServer path which requires a JIT-enable step after every app launch.

If you are outside the EU, use the AltServer method in S1.

Adding emulator sources and installing apps:

AltStore installs apps from "sources" — curated repositories that list available apps. The default AltStore source includes Delta (multi-system Nintendo), Clip (clipboard manager), and others. To install emulators not in the default catalog:

1. Open AltStore → Browse tab → tap Sources (top right) → tap +.
2. Enter the source URL for the emulator you want. Check the emulator's official website for the current source URL — source addresses change after app store policy updates and takedowns. Known sources as of mid-2026:
   • DolphiniOS (GameCube/Wii): check dolphinios.com for the current source.
   • Provenance (multi-system: Atari, Sega, PlayStation, SNK): check provenance-emu.com.
   • GameTrack, UTM, and others: each lists its own AltStore source on their official site.
3. After adding the source, return to Browse — the emulator appears in the list. Tap Get to install.

App limit: Apple's free developer certificate allows up to 3 sideloaded apps at once. If you hit the limit, remove one app via AltStore before installing another. A $99/yr Apple Developer account removes this limit and extends certificates to 1 year.

For a list of what each iOS emulator covers, see Best emulator for iPhone 2026.

Enabling JIT for emulators that need it (DolphiniOS, UTM, PPSSPP JIT mode):

JIT (Just-In-Time compilation) dramatically speeds up emulators that support it, but requires a special enable step on non-EU devices:

1. Launch the emulator app and immediately switch back to AltStore (the app must be running in the background).
2. In AltStore → My Apps → long-press the emulator → tap Enable JIT.
3. Switch back to the emulator — speed improvement is immediate.
4. AltServer must be running on your PC/Mac on the same Wi-Fi for this to work. EU Marketplace users get JIT automatically without this step.

Common errors and fixes:

• "AltServer not found" when refreshing or enabling JIT:
  • Confirm AltServer is running on your computer (check system tray / menu bar).
  • Your iPhone and computer must be on the same Wi-Fi network.
  • On Windows: make sure Apple Devices (or iTunes) is installed and running.
  • Try restarting AltServer and reconnecting via USB once to re-pair.
• "App could not be installed — certificate has been revoked": Apple has revoked the developer certificate. Reinstall AltStore from AltServer (your data is kept) and then reinstall sideloaded apps. This sometimes happens when Apple sweeps free developer certs — it is rare but not preventable without a paid Developer account.
• "Maximum number of apps reached" (3-app limit): Go to AltStore → My Apps → swipe left on an app you no longer need → Remove. This frees a slot without deleting the app from your phone — you are only removing it from AltStore's signing count.
• App crashes immediately after iOS update: iOS updates can invalidate sideloaded certificates. Open AltStore → My Apps → tap the refresh icon to re-sign all apps.
• "Untrusted Developer" when opening a sideloaded app: Go to iPhone Settings → General → VPN & Device Management → tap your Apple ID → Trust. This step is required once per certificate installation.

For more iOS emulators, see Best emulator for iPhone 2026. To install DolphiniOS specifically via AltStore, see DolphiniOS iPhone setup guide.