DNS66 Blocks ads, no root required
There are lots of ways to block Ads on Android without root. DNS66 available from F-Droid (https://f-droid.org/packages/org.jak_linux.dns66/) is a decent one which works providing your not already running a VPN. Personally I use that when not running my VPN along with Firefox and uBlock Origin or Opera Mobile's build in ad blocking, Opera's ad blocking isn't that good on it's own but better than nothing and my VPN software also provides some ad blocking functionaliy.
Biting the hand that feeds IT
