I'm not really sure what I'm looking at here. Is it meant to look a bit hand-drawn, a bit crude and bumpy? If so, that's fine, it's a legitimate aesthetic - although perhaps you could rough the /d up a bit; the inside bowl is too lovely. If not, take a look at the curves on, say, the arches of the /n and the /h.
I can't really speak to the Arabic but it seems (to me at least) cleaner and less crude than the Latin. Compare the smoothness of the /dad-ar with the bumpiness of the /R. I don't know if that's a good match. Maybe tell us a bit more about your design idea?
Are the feet of the /d and /a (and the /h and the /n) supposed to look different? Again if you're going for crude and hand-drawn, that's probably OK.
The outer leg join of the /R looks to be at the wrong angle - should be going in to match the lower part of the bowl, so heading south-west instead of west.
Do you have a full Latin alphabet yet or are you still developing it?
Hrant, the issue is one of design and intent. If you think you're ever going to go cross-platform, you make use of one of the cross-platform UI libraries such as Qt (which I think is what Fontlab uses). You also make sure you use a programming language that works on all the platforms you want to support.
If cross-platform isn't an intent from the start, then you work with naive UI libraries and languages, which can be more efficient, both in terms of programming time and runtime performance.
Glyphs is written in ObjectiveC and tied closely to the Mac API and graphics widgets. Porting to another system would be more than just rewriting all the graphics components (which in a graphics app is pretty major) but would also involve rewriting in a different programming language, as auslander support for ObjectiveC isn't great.
Even if you do intend a cross-platform app from the get-go it isn't a zero cost proposition. Cross platform widget sets can be pretty clunky as they are trying to map ideas to multiple different user interface conventions at the same time, and there's often advantages to working with the libraries provided by a single operating system - cross platform means you have to reimplement a lot of that stuff yourself to have a consistent interface to it.
So I think Glyphs being Mac-only is a legitimate design choice.
Right. What this is likely to produce is: 1) Kana designs without a matching kanji set (unusable) 2) Designs with a relatively small kanji coverage (unusable) or 3) Designs produced by running a filter over another font.
Hopefully the MyFonts team will have enough experience to pick up on that kind of thing...