If you're looking for a simple network utility app you might want to give Net Swiss Knife a try on your Windows Phone. Net Swiss Knife has four main tools plus access to your Windows Phone network settings.
With Net Swiss Knife you can scan a local network by IP Address, conduct a DNS query, run a WHOIS search and set up a Wake-On-LAN command. Input is straight forward and from the three-dot menu you can access a series of walkthrough tutorials and your Windows Phone network settings.
Net Swiss Knife has the ability for reverse DNS queries and auto WHOIS server selection (just leave the server field blank on the search screen). Queries are also possible to nameservers other than by IP address. There's really not much to Net Swiss Knife but it does what it does well. The app ran smoothly and pulled up search results without delay.
Net Swiss Knife isn't going to be for everyone but if you need a collection of network tools, it might be worth checking out. Net Swiss Knife is a free app for your Windows Phone and you can grab it here at the Windows Phone Marketplace.