Re: [Tips and Information] Privacy and How to Stay Anonymous Online
Not only our location,our cameras,gallery,file manager and everything can be controlled by someone remotely because we gave them the access to do while installing an app whether its from app market or private sites,so we are not having any privacy as we think. 
Yeah, you're right but apps will ask you first if you want to allow them to use your camera, file and etc... or not. Some apps can be able to use without allowing them but some are not. 
You can always disable them in settings if you doubt someone controlling your SmartPhone with some apps.
I always disable them to make sure my phone files and front camera safe and use a fake GPS app(I use this before in Pokemo GO to make a fake location)
Or use your Smartphone offline and never connect it to the internet.