This application is dealing with lock screen features. So it will read incoming call state to close lock when call will come and when call will end lock will be active again.
permission.READ_PHONE_STATE
Allows read only access to phone state, including the phone number of the device, current cellular network information, the status of any ongoing calls, and a list of any Phone Accounts registered on the device.
Use of this permission : This permission is much necessary for this application because when incoming phone call will receive then lock will close and after call end then lock will activate again. With the help of this permission call status will detect and application will work properly. This permission will not send device data anywhere. This is secured and use for lock screen functionality only.
permission.SYSTEM_ALERT_WINDOW
Use of this permission : Lock Screen Love have priority to show on front of all other applications so call security application need some permission to show over other applications.
permission.ACCESS_NETWORK_STATE
Use of this permission : This permission is necessary for this application because this app is totally free and developer have only one option to make revenue is monitization and when developer wants to show ads in this app application internet access will be needed.
NOTE:
This application is basically an effort to make lock screen pattern code application. This lock screen is not 100% professional security lock for android devices but it is an effort to develop a lock screen with fancy graphics.
If you have further queries then you can contact on elixerapps@gmail.com