Android Marshmallow lets you control the permissions each app can request to have access to. To control and manage app permissions on HTC 10 running Android 6.x Marshmallow, do as follows:
1. Open the Settings application on your HTC device
2. Scroll down to the Phone settings and tap to open the Apps settings
3. Now, under the list of available apps on your HTC 10, tap the application you want to check the permissions and decide whether to grant a specific permission to it or not.
4. Tap the Permissions option
5. The permissions for this specific application is now shown, and the toggle button next to each permission lets you grant/un-grant the access.
What if you want to see, the list of applications with the Location permission? Well, to view the list of application with the same granted permission, do as follows:
1. Open the Settings app, scroll down to the Phone settings and tap to open the Apps settings
2. Hit the 3-dot icon followed by the Configure Apps settings
3. Touch to open the App Permissions settings
4. Tap on the specific permission you want to look deeper
5. And there you should see the list of applications which have this specif permission in common.
Note that, by default System services are not shown. To show system, simply tap the 3-dot button and specify whether to Hide System or Show System