If you want a specific device to bypass Pi-hole and use another DNS server you can do it by adding an exception to /etc/dnsmasq.d/04-bypass.conf.
Append something like this to the bottom of the file.
This of course also works with dnsmasq on it’s own, you can add something like the below directly to the dnsmasq.conf file.
## This will go straight to Googles DNS Servers.
dhcp-option=tag:googlesdns1,6,8.8.8.8
dhcp-option=tag:googlesdns2,6,8.8.4.4
## Your Device that goes to Google DNS
# dhcp-host=MA:CA:DD:R:ES:SS,set:googlesdns1
dhcp-host=10:8E:E0:88:E3:F0,set:googlesdns1 # phone
dhcp-host=F0:1D:BC:07:27:02,set:googlesdns1 # pc
A full example below from here:
## The contents here bypass pihole by mac address
## This will go straight to Googles DNS Servers.
dhcp-option=tag:googlesdns1,6,8.8.8.8
dhcp-option=tag:googlesdns2,6,8.8.4.4
## This will go straight to Opendns Servers.
dhcp-option=tag:opendns1,6,208.67.222.220
dhcp-option=tag:opendns2,6,208.67.222.222
## OpenDNS FamilyShield
dhcp-option=tag:opendns3,6,208.67.222.123
dhcp-option=tag:opendns4,6,208.67.220.123
## Level3 DNS
dhcp-option=tag:Level3DNS1,6,4.2.2.1
dhcp-option=tag:Level3DNS2,6,4.2.2.2
## Comodo Secure DNS
dhcp-option=tag:ComodoSecureDNS,6,8.26.56.26
dhcp-option=tag:ComodoSecureDNS,6,8.20.247.20
## Norton
## P1 - malware, phishing schemes, and scams.
dhcp-option=tag:norton1,6,199.85.126.10
dhcp-option=tag:norton2,6,199.85.127.10
## P2 - Pornography
dhcp-option=tag:norton3,6,199.85.126.20
dhcp-option=tag:norton4,6,199.85.127.20
## P3 - Security + Pornography + Other
dhcp-option=tag:norton5,6,199.85.126.30
dhcp-option=tag:norton6,6,199.85.127.30
########################################################################
## Instructions
## First set your tag, and dns server.
## dhcp-option=tag:YOURTAGHERE,6,IPADDRESSOFDNSSERVER
## You then simply need to replace MA:CA:DD:R:ES:SS
## I have set up the standard DNS servertags above.
## Below are examples of how to set a mac address to bypass pihole.
## Your Device that goes to Google DNS
#dhcp-host=MA:CA:DD:R:ES:SS,set:googlesdns1
## Your Device that goes to OpenDNS
#dhcp-host=MA:CA:DD:R:ES:SS,set:opendns1
## Your Device that goes to custom DNS Server
#dhcp-host=MA:CA:DD:R:ES:SS,set:YOURTAGHERE