Blokada - The best ad blocker for Android. Free and open source.
XPrivacyLua - Really simple to use privacy manager for Android 6.0 Marshmallow and later (successor of XPrivacy).
BLOCK THIS! - Block This 3.0 is a FREE and Open Source ad blocker for Android that works in all apps and browsers!
App Ops - modifies the settings of "appops" in Android system
AdShield.ai - AI-powered placement exclusion lists for Google Display campaigns
PilferShush Jammer - Block unwanted use of onboard microphone