Can I access my local web server(IIS)from my smart phone?

As long as the local web server (IIS) is working and you can browse a file on the server from your browser you should be able to browse the same file on your smart phone provided you access the IP Address of your computer hosting the IIS.
You can find the iPv4 address of your computer by using the ipconfig command :
------
C:\Users\Owner>ipconfig
Windows IP Configuration
Ethernet adapter Ethernet:
   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :
Wireless LAN adapter Local Area Connection* 1:
....
....
....
Wireless LAN adapter Wi-Fi:
   IPv4 Address. . . . . . . . . . . : 192.168.0.10
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Here is a partial view of my default site showing the content SVGCode.html, an interactive HTML5 page:

This is how it appears on a Microsoft Edge 15 browser:

This how it is called on my Microsoft Lumia 950 phone using the IP Address:

Note:  Although I entered the IP Address, the phone translated it to the computer name.

If it does not get displayed check the firewall and make sure this item is checked:

The computer was a Dell Laptop running Windows 10 Professional and the smart phone was a Microsoft Lumia 950 both on the same Wi-Fi network.