Nope.
You can add a vote to this old feature request, the more the better: Folders For Organising Projects
I try to keep clones and experiments and apps with clone link in the forum in my personal free account, and work related stuff in the business account.
Other than that, I have learned to use long app names. The real production apps have their real name, not too long, the experiments, clones and other apps that I will likely rarely visit again have long names that make up for the lack of folder hierarchy. Kinda.