I think daviesmkareee is on point below.
The word "habari" is both singular ("a piece of news") and plural. "ya" is used when it's singular, and "za" when it's plural. However, when it's pretty much meaning "How are you today?" there's not a whole lot of difference between them. Perhaps a fluent speaker can explain any subtle nuances. There are about 1 2/3 times as many Google results (with quotation marks, so finds the exact phrase) for the form with "ya" for whatever that's worth.
wow this is fun but confusing. And why if representing English is the american flag? English is well... english! I know there are more americans in the world than us brits but shoudnt the flag representing a language should be the origin country? It should be the union flag of britain? What does everyone else think
Please check with him again, because "leo" definitely translates as "today":
leo nm [i-] = today.