There is a question mark, shouldn't the correct translation be "How is the evening, Juma?"?
Yes, except that a Swahili speaker wouldn't expect you to actually tell them how you are. You would always answer with "Habari nzuri" or simply "Nzuri". In English it is also possible to answer that you are not doing fine, but in Swahili this is (almost?) unheard of. It is used purely as a greeting, and is therefore best translated with an equally common English greeting, and so "Good evening, Juma!"
You should not have to put the word "your" in the sentence to be correct
It's a common way to greet in Kiswahili. You're asking if the person has any news. And if the time is evening, you would ask for news of the evening. The common response would be to say you have good news.
Thank you for your erudite explanation. I realize that understanding the culture and mindset of the people, helps a great deal in learning the language. In Russian, for instance, they have an entirely different way of expressing things than they do in English or any or the romance languages, or germanic languages as well. It seems very difficult, but extremely interesting, as this is!
Putting it in the end would place emphasis - you can do it f.ex. when calling him to then ask the question. It also has to do with personal preference, but I have noticed that it is more casual to place the address at the end, placing it in the beginning could happen to get attention, like being in a large group of people and Juma has not talked yet, so you address him specifically to hear from him.
Mine hasn't worked since installing this app, literally been trying to just pronounce the words the way I think they're pronounced