Applying to shows used to be a mess of slides and checks and SASEs for us artists. Then came along ZAPP which made our lives so much easier - especially applying while on the road!
Since then a lot of smaller festival application software has arrived. It's been a while since I've been on the circuit, but I remember long ago Bonita Springs was using something other than ZAPP.
These days, what has been the easiest and/or most difficult system for you to navigate when applying for in-person and virtual shows? I'm looking for one that works well for artists but doesn't break my budget (for my little art fair.)