Starting with v320(beta coming soon), you would be able to create subnets within subnets on the fly and have an overall better experience with IP address management in device42. Some of the upcoming features are discussed below.
As shown in the gif above, you would be able to create nested subnets within a subnet quite simply by just entering the mask bits and next available subnet would be automatically created for you.
Optional vs Required fields for subnets
Only network and mask bits are now required when creating a subnet and name becomes an optional field. We are changing the furniture a bit on the page to reflect this change.
Breadcrumbs and nested subnets
Simple navigation within nested subnets using breadcrumbs.
VRF groups and overlapping address ranges
Device42 has always allowed adding overlapping address ranges across subnets. This would be much simpler now with use of VRF groups and nested subnets, where we would be able to enforce unique IPs on a single VRF group and give you a better idea of usage etc.