Avast uses tracking as do most other apps.

Windows8 wants all users to agree to Geo location tracking so that the apps can serve you content pertaining to yur current location.

Android (Google) phones know your location 24/7 and many available apps track not only your position, but read your contacts, messages and log your phone calls.

Always read what permissions applications require, some are very intrusive.

Assuming you have an Android smart phone , look for privacy applications. I also use Android Assistant, that helps clear memory, data etc. it has many tools and will show you what permissions applications use.