Mirai Solutions has some tips on cleaning up Shiny apps:
How to apply the spring cleaning principles and advanced programming to your Shiny App.
1. Deep breeze and allocate some time
Do not avoid spring cleaning simply because you don’t know where to start from. Prioritize some time for the task and get inspired by our following points.
Click through for advice on tools and processes to make this code easier to understand. H/T R-Bloggers