How to override DHCP client identifier

I'm running a DHCP/DNS server with dynamic DNS on Debian 9 (Stretch) How do I override a clients DHCP identifier and place in my own custom value? E.g Android phones on the network identify themselves as androidxxxxx and there are a few of them on the network. This results in a dynDNS update where I can't tell apart the different phones. I want to override the value the android client send and have a custom DNS record.