Back again... In answer to PadKeys question about whether something obscure like typesetting etc is generating requests for symbols like the NBSP and NBHY, the emphatic answer is no. Nor has it anything to do with the Web or markdown.

This is for ordinary word processing. It’s to stop 4 September or 03‑06‑2016 breaking at the end of a line. The symbols ' and " represent minutes and seconds (of angle or time), or feet and inches—they are not apostrophes or quotation marks. Yes, that was an emdash there.

And the extended Latin letters are so that we can can spell foreign words and names correctly at last, and (with a little bit of extra knowledge) even have a better stab at correct pronunciation!

I don't find over, say, 6 press and hold characters being cluttered at all, as long as the arrangement is carefully planned. The whole keyboard width is available after all.

For instance, I have recently required ě, ů, ř and ş. If they're not available in the obvious places, I have to change keyboards. That's much more of an imposition than any perceived clutter.

The obvious press and hold option that I have never seen implemented is the = key. Press and hold usually brings up the + symbol, but isn‘t it logical to put the ×, ÷ and − (minus symbol, not endash) there as well?

I highly recommend the previous suggestion for the non-breaking hyphen to be available from the - key. The other item desperately needed here is the non-breaking space.

As a general comment, the idea of reproducing the mechanical keyboard layout is fine for those who prefer it, but the beauty of the on-screen keyboard is the vastly expanded and better organized character set it allows.

Use case for soft-hyphen and zero-width space: these allow you to manually define breakpoints in the middle of a word so that rendering software knows that it can wrap the text there. The regular hyphen does this too, at the cost of always having a hyphen in the middle of the word; the regular space does it by breaking the word into two words.

• ZWSP: when you don't want a hyphen, but you want it to be able to wrap.
• soft hyphen: when you want a trailing hyphen on a wrap, and no hyphen on a non-wrap.
• regular hyphen: when you always want a hyphen, and you want it to be able to wrap.
• no-break hyphen: when you want a hyphen there, but you don't want it to wrap.

Use case for a non-breaking hyphen is when you want a hyphen in the middle of a word, but don't want it to wrap there: the two parts of the hyphenated word need to be on the same line. Likewise, the NBSP gets used extensively in web pages, any time you need to ensure that two adjacent words on the same line. You can do it by inserting a “ ” Entity where a space would normally be; but that's a workaround for those who don't have the direct access to the NBSP character that we're requesting.

I use WJ to break encoding: for instance, “_this_” is rendered by Markdown in italics and without the underscores; inserting a WJ between the first underscore and the “t” lets me force it to render with the underscores and without the italics.

Finally, the Wide Space is useful when using mostly-fixed-width fonts that nonetheless render spaces more narrow than other characters. Admittedly, this is a rare case, and I wouldn't be offended if it's dropped.

As for the concern about cluttering the popups: in general, I'm OK with any given popup having as many as six choices on it; more than that is cluttered, though in some cases (such as the currency symbols) the clutter is necessary. But certainly, three or four choices isn't cluttered.

I'm curious as to the use case for the non-breaking and other "special-handling" characters. Is it for some kind of copy-editing? Is there some sort of type-setting app that is commonly used? I have a slight worry about cluttering the popups too much with menu entry characters that only a small subset of users will ever use.

I don't see much need for “advanced” press-and-hold features to be switched off: if you don't press and hold a key, you won't even know that they're there.

I would definitely like to see the following whitespace characters associated with underscore:

• ZWSP (200B: Zero-Width Space)
• WJ (2060: Word Joiner)
• NBSP (00A0: No-Break Space)
• wide space (3000: Ideographic Space)

Likewise, I'd like to see the following two hyphen variants associated with the hyphen:

• 00AD (Soft Hyphen)
• 2011 (Non-Breaking Hyphen)

In all of these cases, some mechanism needs to be put in place to make the pop‑up keys visually distinctive.

I recommend to include the non breaking space and non breaking hyphen as press and hold feature. To ensure ease of use there should be a switchable option to aktivate/deactivate advanced press and hokd features.

Be thankful I didn't start listing associations for keys on the Options keyboard… :)

Top priorities for me would be hyphen, quote, apostrophe, period, and asterisk; I make extensive use of most of the characters I associated with those five keys. (I could see starting the asterisk out with just ×, ⋅, †, ‡, and §. The first two aren't available on your keyboard at all right now, so their inclusion is vital.)

Of the rest, I'd go with #, $, and % next — # for the delta, $ for cents, and % for degrees; I don't use these nearly as often, but I do use them occasionally.

The others are nice to have but rarely needed.

Heh, OK thanks. We might start with a subset of these. ;-)

Remember, you asked for it.

• “.”: “…”
• “`” (the upper left key): various accents and marks (the kind that you have colored blue on the options keyboard).
• “~”: ¬
• “#”: ∆, ∇. My rationale is that all three of these tend to serve as prefixes.
• “$”: various currency symbols.
• “%”: ‰, ‱, °, ′, ″. My rationale for the last three is that just as % gets postfixed to a number, so do degrees, minutes, and seconds.
• “^”: various arrows.
• ampersand (&): various logical operators (e.g., ∧, ∨, ⊻)
• asterisk (*): ×, ⋅, ∗, ∘. Also the following set of symbols, in this order: “†”, “‡”, “§”, “‖”, “¶”, “☞”. Reason: when doing footnotes, that's the traditional order for the second through seventh footnotes (the first being an asterisk).
• “/”: division slash, division sign, fraction bar.
• “1”: ¹, ₁, ½, ⅓, ¼, ⅕, ⅙, ⅛
• “2”: ², ₂, ⅔, ⅖
• “3”: ³, ₃, ¾, ⅗, ⅜
• “4”: ⁴, ₄, ⅘
• “5”: ⁵, ₅, ⅚, ⅝
• “6”: ⁶, ₆
• “7”: ⁷, ₇, ⅞
• “8”: ⁸, ₈
• “9”: ⁹, ₉
• “0”: ⁰, ₀, ∞
• underscore (_): non-breaking space; possibly other kinds of spaces?
• “=”: ≡, ≈, ∝
• “+”: ±, ∓
• “[”: left ceiling (⌈), left floor (⌊).
• “]”: right ceiling (⌉), right floor (⌋).
• colon: ratio (∶), proportion (∷).
• semicolon: “∵”, “∴”
• “<”: ≤, ≪, ≮, ≰, ⋘, ⊂, ⊆, ⊄, ⊈.
• “>”: ≥, ≫, ≯, ≱, ⋙, ⊃, ⊇, ⊅, ⊉.