• Determine What Permissions Your App Needs
• Normal Permissions

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Every Android app runs in a limited-access sandbox. If an app needs to use resources or information outside of its own sandbox, the app has to request the appropriate permission. You declare that your app needs a permission by listing the permission in the App Manifest.

Depending on how sensitive the permission is, the system might grant the permission automatically, or the device user might have to grant the request. For example, if your app requests permission to turn on the device’s flashlight, the system grants that permission automatically. But if your app needs to read the user’s contacts, the system asks the user to approve that permission. Depending on the platform version, the user grants the permission either when they install the app (on Android 5.1 and lower) or while running the app (on Android 6.0 and higher).

Determine What Permissions Your App Needs

As you develop your app, you should note when your app is using capabilities that require a permission. Typically, an app is going to need permissions whenever it uses information or resources that the app doesn’t create, or performs actions that affect the behavior of the device or other apps. For example, if an app needs to access the internet, use the device camera, or turn Wi-Fi on or off, the app needs the appropriate permission.

Your app only needs permissions for actions that it performs directly. Your app does not need permission if it is requesting that another app perform the task or provide the information. For example, if your app needs to read the user’s address book, the app needs the READ_CONTACTS permission. But if your app uses an intent to request information from the user’s Contacts app, your app does not need any permissions, but the Contacts app does need to have that permission.

System permissions are divided into several protection levels. The two most important protection levels to know about are normal and dangerous permissions:

Normal permissions cover areas where your app needs to access data or resources outside the app’s sandbox, but where there’s very little risk to the user’s privacy or the operation of other apps. For example, permission to set the time zone is a normal permission. If an app declares that it needs a normal permission, the system automatically grants the permission to the app.

Dangerous permissions cover areas where the app wants data or resources that involve the user’s private information, or could potentially affect the user’s stored data or the operation of other apps. For example, the ability to read the user’s contacts is a dangerous permission. If an app declares that it needs a dangerous permission, the user has to explicitly grant the permission to the app.

Normal Permissions

Many permissions are designated as PROTECTION_NORMAL, which indicates that there’s no great risk to the user’s privacy or security in letting apps have those permissions. For example, users would reasonably want to know whether an app can read their contact information, so users have to grant this permission explicitly. By contrast, there’s no great risk in allowing an app to vibrate the device, so that permission is designated as normal.

If an app declares in its manifest that it needs a normal permission, the system automatically grants the app that permission at install time. The system does not prompt the user to grant normal permissions, and users cannot revoke these permissions.

As of API level 23, the following permissions are classified as PROTECTION_NORMAL:

ACCESS_LOCATION_EXTRA_COMMANDS
ACCESS_NETWORK_STATE
ACCESS_NOTIFICATION_POLICY
ACCESS_WIFI_STATE
BLUETOOTH
BLUETOOTH_ADMIN
BROADCAST_STICKY
CHANGE_NETWORK_STATE
CHANGE_WIFI_MULTICAST_STATE
CHANGE_WIFI_STATE
DISABLE_KEYGUARD
EXPAND_STATUS_BAR
GET_PACKAGE_SIZE
INSTALL_SHORTCUT
INTERNET
KILL_BACKGROUND_PROCESSES
MODIFY_AUDIO_SETTINGS
NFC
READ_SYNC_SETTINGS
READ_SYNC_STATS
RECEIVE_BOOT_COMPLETED
REORDER_TASKS
REQUEST_IGNORE_BATTERY_OPTIMIZATIONS
REQUEST_INSTALL_PACKAGES
SET_ALARM
SET_TIME_ZONE
SET_WALLPAPER
SET_WALLPAPER_HINTS
TRANSMIT_IR
UNINSTALL_SHORTCUT
USE_FINGERPRINT
VIBRATE
WAKE_LOCK
WRITE_SYNC_SETTINGS

除去normal permissions，其他的就是dangerous permissions.