I just suggested that Dropbox (iOS) add preview capabilities to .jl files just like it has for Python’s .py files and MATLAB’s .m files. As an old idea was closed for voting due to inactivity, I felt it might be a good idea to rally support here 
The lack of this feature in Dropbox has been a nuisance for me these last few days while I have started learning Julia.
Please go to Add preview capabilities for .jl (Julia) files - Dropbox Community and vote 