Start the download. Tap the gold button above. If Chrome warns "This type of file can harm your device", choose Download anyway — that warning shows for every APK and isn't detecting a problem. At 3.8 GB this takes a while; if it stops, use Resume in your Downloads rather than tapping the link again.
Open the file and tap Install. Tap the finished
download, or find it in Files → Downloads → SpectreRO.apk.
Allow the permission when asked. If you see "your phone isn't allowed to install unknown apps from this source", tap Settings in that popup, switch on Allow from this source, then press Back — the install continues.
Get past Play Protect. If it says "Unsafe app blocked" or "App scanned", tap More details → Install anyway. This appears because we're outside the Play Store.
Wait, then log in. Installing an app this large takes a few minutes and may look frozen — don't reboot. When it finishes, open Spectre RO and sign in with your normal account.
Only needed if the popup in step 3 never appears.
Android 8 and newer:Settings → Apps → Special app access → Install unknown apps → Chrome → Allow from this source
Samsung: Settings → Apps → ⋮ (top right) → Special access → Install unknown apps
Xiaomi / Redmi / POCO: Settings → Apps → Manage apps → Chrome → Install unknown apps
Oppo / realme / vivo: Settings → Password & security → System security → Install unknown apps
Android 7 and older: Settings → Security → Unknown sources
| "There was a problem parsing the package" | The download didn't finish. Delete the APK and download it again. |
| "App not installed" | Usually not enough free space. Clear some and retry. If you installed a SpectreRO APK from elsewhere before, uninstall that first. |
| Install looks frozen | Normal at 3.8 GB. Give it several minutes and don't reboot. |
| Download restarts at 0% | Resume from the Downloads screen instead of re-tapping the link. |
| Xiaomi blocks it | MIUI scans APKs and can block the first attempt. Open the notification and choose to install anyway. |