Swahili in Arabic Script
I have just started the Swahili course, which I intend to finish, and was trying to find research into the Arabic script that Swahili uses. I know how to read and write it, I just don't know when to use it!
Is the Arabic script used at all nowadays, or is it only in old texts?
Shukrani / شُكرَنِ
I don't think it is any longer in general use, although it might still be used in contexts such as religious scholarship, for example. From what I gather, it is much less phonetically precise than the Latin script, so there would be little sense in learning it in the early stages.
I think that there are actually drawbacks phonetically to both systems. However I think that the Latin script is more accurate. Certain diacritics in the Arabic script made it more accurate, however they dipthongs weren't written (mtoto and mbobo are written as مْتْ and مْبْ. Notice how they both begin identically?
If that is true, your examples spell "moto" and "mobo". There is only one t and only one b. In Arabic, the sukun (the little circle above the consonants in your examples) indicates that there is no vowel following the consonant. So, in Arabic, your examples would be interpreted as "mt" and "mb". Swahili has more distinct vowel sounds than Arabic, so they might have adapted the sukun for that purpose.
Then I would expect متْتْ and مبْبْ for mtoto and mbobo.
I don't know anything about the Swahili version of the Arabic script. I only know Arabic script as it is used in Arabic. But, from that perspective, your examples seem a little odd. ;)
I don't think you're ever likely to see Swahili written in Arabic script unless you're reading a very old historical document. Virtually all Swahili writing nowadays is in Roman script. It's kind of like Turkish or Indonesian that way - there might be historical use of Arabic script but modern documents don't use it. My Swahili teacher in college never even mentioned Arabic script for writing Swahili.
Speaking from personal experience, in Kenya, Tanzania, Rwanda & Uganda you will only ever encounter Swahili written in the Latin alphabet. The Muslim population does use Arabic, written in Arabic script, for religious purposes. Similarly, in densely Muslim areas you will frequently hear Arabic greetings. While historic documents do have Swahili written in Arabic script, modern written Swahili solely uses the Latin alphabet.
I am a native Tanzanian. And you are absolutely right. We no longer use Arabic script for Swahili . I am a Muslim myself and like you stated, we only use Arabic script for Arabic when it comes to religious purposes. If you want to learn conversational Swahili, no need to learn Arabic script. I have some tutorials for this in my YouTube channel: https://www.youtube.com/watch?v=p6XCkGg3zCQ&t=7s
There are (or were) a few books around on classical Swahili poetry in which the author reproduces the Arabic script from some original source or sources, then gives his Swahili transliteration (often contested by other scholars), and finally his (frequently flowery) translation of the poem(s) in English. The best example I can think of is Al-Inkishafi (The Soul's Awakening), William Hichens, Oxford University Press, Nairobi: 1972, (first published 1939 by Sheldon Press). The original poet, Sayyid Abdalla bin Ali bin Nasir lived sometime in the period 1720-1820, apparently on Lamu or the islands north of Lamu. The poem in addition to being a couple hundred years old, is also written in the Kiamu dialect. I have glossed over a great deal of scholarly detail here, and admit to having no particular knowledge, just what I have read here and there.
I don't know if this kind of study is included in any curricula at the present time. I would think it would have to be a very advanced course (graduate level) in Swahili literature, and I don't know where something like that would be offered.