By Selecting the starting IP address this iPhone App will allow you to specify the amount of Routers in your network and how many devices per router you require. They do not have to be uniformed and it will calculator the subnet size and lay out all the subnets in a view and allow you to email a table of the results.

Depending on the usage of app, future versions will include:

ASN calculation for Multicast addresses and visual depiction of network plan.

Assign device counts to multiple subnets

Also future apps will include IPv6 and Bandwidth