Being a native Arabic speaker, it never occurred to me how complicated the language is compared to many others. I learned to speak it, read it, and write it ever since I was a kid, so I rarely notice its idiosyncrasies and instead simply think of all of it as second nature. If you come from an another background though, Arabic can be a daunting language to learn, but that's exactly what Duolingo has taken on. The service now offers Arabic courses for English speakers in its apps and on its site.
Duolingo explains all the difficulties of learning Arabic and thus all the challenges it had to face when creating a course for it. Not only is there an all-new alphabet, but every letter can be written differently depending on whether it falls at the start of a word, in the middle, or at the end. Making matters worse, Arabic writing has very few vowels and relies on consonants with often inferred "accents," so a written b can be pronounced as ba, buu, bee, or a silent b.
There are also new phonetical sounds to learn and some important subtle differences (k versus hard k, s versus hard s), as well as many grammatical differences compared to latin languages. For example, both the single and plural "you" are gendered, so when you say "you run," your verb will be different depending on whether you're talking to a male or female person(s).
All those differences make Arabic less than ideal for learning through an app-based course, but Duolingo says it has created a special approach for it. There are lots of phonetic exercises to teach learners how to properly pronounce letters, a methodical introduction of alphabet letters that doesn't overwhelm them, and focus on pronouns so that the confusing "you" is easier to grasp when doing translation exercises. It also had to center the course on Modern Standard Arabic and forego any regional dialects, as those are widely varied and more complicated to teach.
If your interest is piqued by this wonderful and confusing language that is spoken by over 400 million people worldwide, you can start learning it right away. The course is available today and it shouldn't be long before you learn what a hard k, s, or d is and understand why when you hear native Arabic speakers, it always sounds like they're angry and about to start a fight.