I don’t use any app at the moment.
To prevent DNS leaking, this is what I do.
- Go to Android Settings
- Go to Wifi & Internet
- Go to Private DNS
- Select Private DNS mode > Private DNS provider hostname > Type there
one.one.one.one
I am sure, if you run test next time there won’t be any leak. All DNS request will be answered from Cloudflare server only not your ISP default one.