Find out service’s versions which are running on remote hosts with the “-sV” option.

sudo nmap -sV 192.168.1.69

result:

Starting Nmap 6.40 ( http://nmap.org ) at 2016-07-08 01:18 BST
Nmap scan report for peter-laptop-1 (192.168.1.69)
Host is up (0.000017s latency).
Not shown: 997 closed ports
PORT    STATE SERVICE     VERSION
80/tcp  open  http        nginx 1.4.6 (Ubuntu)
139/tcp open  netbios-ssn Samba smbd 3.X (workgroup: PETER-LAPTOP-1)
445/tcp open  netbios-ssn Samba smbd 3.X (workgroup: PETER-LAPTOP-1)
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel
 
Service detection performed. Please report any incorrect results at http://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 13.57 seconds