Permission Is Only Granted to System App

Permission is only granted to system app

In Eclipse:

Window -> Preferences -> Android -> Lint Error Checking.

In the list find an entry with ID = ProtectedPermission. Set the Severity to something lower than Error. This way you can still compile the project using Eclipse.

In Android Studio:

File -> Settings -> Editor -> Inspections

Under Android Lint, locate Using system app permission. Either uncheck the checkbox or choose a Severity lower than Error.

Permission is only granted to system app, in Manifest

MODIFY_PHONE_STATE permission is granted to system apps only.

For your information, there are 2 types of Android apps: system & user

User apps are just all your normal app installations through the Google Play Store, Amazon Appstore or sideloading. These go into the /data partition of your Android phone, which is the part of the internal memory made available for user data and apps.
System apps are basically the apps that come pre-installed with your ROM. In a standard Android user environment, the user doesn’t have write access to the /system partition and thus, installing or uninstalling system apps directly isn’t possible.
In order to install an app as a system app on your Android device,
your device must either be rooted or have a custom recovery installed (or both).

That being said, that error is actually wrong because you have a valid code and compilation should work. It would be better if it gave a warning instead. In Eclipse you can easily fix it. Just go to:

Window -> Preferences -> Android -> Lint Error Checking.

Find ProtectedPermission from the list and set the severity to something other than error(info for example). This way your project will still compile.

Is android.permission.WRITE_SETTINGS only granted to system apps?

As stated by user passsy in the stackoverflow question provided by Brian, android.permission.WRITE_SETTINGS has a android:protectionLevel of "signature", which makes the permission unavailable for use in user applications since API level 23.

See https://developer.android.com/guide/topics/manifest/permission-element#plevel for the description of protection levels for permissions.

I cannot grant the following permission on my app..Kindly suggest any alternative?

Permissions with the protection level signature or signatureOrSystem
are only granted to system apps. If an app is a regular non-system
app, it will never be able to use these permissions.
So,what should i do now?

If your app is expected to run on non-rooted devices, then you're simply doomed - you can do nothing, unless you have platform keys to sign your app with it.

Alternatively, you may narrow your audience to rooted devices only but that would allow you to do what you want incl. using features usually reserved for the platform or system apps ony.

Finally you may rethink your approach. Perhaps what you want to do can be achieved other way, w/o need of elevating app privileges.

permission is only granted to system application

From Android Documentation about permissions:

public static final String INSTALL_PACKAGES

Added in API level 1
Allows an application to install packages.

**Not for use by third-party applications.**

Constant Value: "android.permission.INSTALL_PACKAGES"

system app permission issue

How will I give permission at install time to it won't ask for any
permission at runtime?

If you are running your app on OS version >= Android M (API 23) and targetSdkVersion is set to >= 23, permissions falling under dangerous category (storage/location permissions fall under this category) have to be granted at run-time. Even System apps are not exempted from this request.

For generic apps only the normal-level permissions are granted at installation time. Since your app is signed with firmware key the advantage it gets is, the normal-level as well as signature-level permissions will be granted at installation time. Refer to official document for more details.