Four Alefs and a Look-Alike: ا, أ, إ, آ, and ى
These five keys are not stylistic variants of each other — each is a distinct, required spelling choice. ا (3rd row) is the plain long vowel. أ and إ (4th row) carry a hamza above or below to mark a glottal stop at the start of a word. آ (4th row) marks a long vowel following that glottal stop. ى (4th row, alef maksura) looks like an undotted yeh but functions as a vowel, typically at the end of a word — don't confuse it with ي (3rd row), which is a full consonant-and-vowel letter with two dots underneath. Picking the wrong one of these five is a genuine spelling error, not a font rendering issue.
All Nine Diacritics Live in the Last Row
The 5th row is entirely harakat — the small marks that indicate short vowels and pronunciation details, plus ئ at the start. You won't need most of them for everyday typing: newspapers, websites, and casual writing are conventionally left unvocalised. They matter when you're producing Quranic text, children's educational material, or anything else where the exact pronunciation needs to be marked explicitly. Everything you need for that is on this one row, so there's no need to hunt for it elsewhere in the layout.
The Tatweel Key: Stretching Letters Without Changing the Word
ـ (5th row, just before Space) is tatweel — a purely visual elongation character that stretches the connection between two letters. It doesn't add a sound, change spelling, or affect pronunciation; it exists for justified text and calligraphic stretching. Used sparingly it's a legitimate typesetting tool; used heavily it looks unusual to Arabic readers, so most everyday writing skips it entirely.
Why Arabic Text Sometimes Displays Backwards Elsewhere
Arabic is a right-to-left script, and the text this keyboard produces is correctly encoded Unicode with normal reading order. If it ever displays reversed, jumbled, or left-to-right after you paste it somewhere, the problem is on the receiving end — an application or field that isn't handling the Unicode Bidirectional Algorithm correctly — not with the text you copied. Pasting into a plain-text field or a different, RTL-aware application usually resolves it immediately.