DLDI (Dynamically Linked Device Interface) files for Nintendo DS homebrew files that allow them to fully communicate with the flash cart device they are running on.
These are generally no longer needed as flash cart manufacturers commonly incorporate automatic DLDI patching in to the system firmware/loader.
Caller -"Everytime I start a Pc game on my S24, playing on a external monitor, someone calls or texts me, n it kicks me out of the game." Customer Support - Click (hangs up)
I found it funny cause many many years ago, had a roommate in college that did this same dumbass branding of the school logo, but it didn't look anything like it after it healed. Just looked like a birthmark.