Being the King of the Infinite Realms didn't really give you many dating options. There were no candidates who weren't committed or completely sincere, and Danny was feeling sensitive those days so he was frustrated. The Observants telling him to get a partner to create a "better future" and offering horrible options was especially infuriating those days, he wished they would stop meddling in his life.
Sam and Tucker, seeing the halfa's frustration did what any friend would do in such a situation: They created a profile for him on a dating app. Although they didn't notice that when they connected it to Technus' Internet the app started taking "candidates" from other dimensions that had it.
Despite not trusting it much at first, Danny eventually embraced the idea and very quickly connected with "Jason Todd" who claimed to be a zombie. Danny thought it was funny and told him he was a ghost, which Jay obviously didn't believe. Ironically, they matched because of the "I died" jokes on their profiles.
The only problem was when Jason asked to meet (he was absolutely convinced that Danny was either homeless or living on the streets due to his refusal to send pictures from home and wanted to feed him) and Danny didn't know how to tell him that he didn't know what dimension he was in.