The NFL does not have an official developmental league after the disbanding of NFL Europe, but that doesn’t mean there aren’t any options for players out there. One interesting option is a fairly new one, and a couple of former Denver Broncos draft picks are participating.
It’s called The Spring League, and it’s based out of West Virginia. They describe themselves this way:
The Spring League was created in early 2016 to serve as an instructional league and developmental platform for professional football talent. All teams conduct practices and “live” exhibition games that are played in accordance to NFL rules.