The host at this IP address is obviously operated by cybercriminals. It is running a malware botnet controller which is being used to control infected computers (bots) around the globe using a trojan horse.
Malware botnet controller located at 20.185.49.145 on port 8081 TCP:
$ telnet 20.185.49.145 8081
Trying 20.185.49.145…
Connected to 20.185.49.145.
Escape character is ‘^]’
$ dig +short myapk.ddns.net
20.185.49.145
Referencing malware samples (MD5 hash):
e7b30a4f73dc310ce4adab699f4e0767 — AV detection: 31 / 71 (43.66%)