1. Why some apps don’t need autostart permission to run background services on Xiaomi devices? #

MIUI’s background restrictions are built to balance battery life and app functionality, but there are several legitimate paths apps can take to run background services without explicit autostart approval:

• Foreground Services: If an app launches a foreground service (paired with a persistent notification), Android’s core framework prioritizes this task. MIUI generally respects this priority, letting the app run in the background even without autostart enabled—this is common for music players, navigation apps, or ride-sharing services that need ongoing operation.
• Default Whitelisted Apps: Xiaomi maintains a built-in whitelist for system apps (like Mi Cloud, Xiaomi Security) and popular partner apps (top social media, messaging platforms). These are deemed essential for user experience, so they’re exempt from autostart restrictions by default.
• System-Managed Scheduled Tasks: Apps using Android’s native APIs such as JobScheduler, WorkManager, or Firebase Cloud Messaging (FCM) can trigger background tasks without autostart. MIUI doesn’t block these because they’re controlled by the Android system, which schedules tasks efficiently to avoid unnecessary battery drain.
• Special Permissions: Apps holding accessibility, notification listener, or device admin permissions often get implicit background access. MIUI allows these apps to run in the background to fulfill their intended purpose—for example, a screen reader needs constant access to function properly.

2. How do some apps get automatically added to the "allowed background autostart" list without user authorization? #

Auto-whitelisting usually happens through one of these scenarios:

• Pre-installed System/Carrier Apps: Any app preloaded on the device (by Xiaomi or your mobile carrier) is automatically added to the autostart list. These are trusted by the OEM, so they skip the user authorization step entirely.
• OEM Partnerships: Apps with formal agreements with Xiaomi (like large banks, top-tier e-commerce platforms) can be configured to auto-whitelist during installation. This ensures the app works as expected without forcing users to manually adjust settings.
• Heuristic Auto-Whitelisting: MIUI uses a heuristic system to track user app behavior. If you open an app daily, use it for extended periods, or rely on it for critical functions (like a work messaging app), MIUI might automatically add it to the allowed autostart list to avoid disrupting your experience.
• Gray Area Workarounds: A small number of apps exploit loopholes—like requesting high-priority permissions (accessibility, device admin) that indirectly grant autostart access, or using MIUI-specific hidden APIs. However, these methods often violate Google’s Play Store policies and are frequently patched in newer MIUI updates.

内容的提问来源于stack exchange，提问作者S.Trathi