We try to hold on to as few logs as possible, the goal of the project is improving privacy. You can read the full policy here: https://developers.cloudflare.com/1.1.1.1/commitment-to-priv...
Reason I ask... I have a one-tap shortcut to turn off WIFI and Bluetooth for leaving home. Would be awesome to turn off WIFI / Bluetooth / turn on Cloudfare with a single tap as I head out the door.
I don't need the battery drain from VPN usage while sitting at home, and already have my DNS routed away from my ISP.