Present tense, "talks". Present participle, "is talking".
This is perhaps a bit of a nuanced point.
"How does Kaʻiulani communicate?"
Answer: She talks on the phone (instead of mailing a letter).
The present participle answers this question:
"What is Kaʻiulani doing (right now)?"
Answer: She is talking on the phone.
See what I mean by nuance? In normal conversation, "is talking" is fine. It depends on how exact DL wants to be.
What's interesting is that speak is "E (command) 'ōlelo (language)" so it would, in a sense, be "use the language" while kama'ilio, though the parts don't dictate this, could possibly be "use your voice in a non-singing manner" Pretty much interchangable, but an interesting thing to consider.