All platforms listed above.
::drum roll…::
Oct 30th launch date is confirmed. One minute after midnight, Eastern time.
One silly question: will it be available worldwide?
Yes.
Except that you said "All platforms, not “All the above platforms”. Nice bait and switch attempt of your statement, though.
No one implements their game on all platforms. His meaning was clear enough.
Yes, you have sussed my malefic plan to get every Windows Phone user to buy a game without realizing that there is no Windows Phone Glulx interpreter.
(There goes my Nobel Beet^H^H^H^H Videogame Prize.)
Actually I have no idea what the Windows Phone situation is. Anyone know?
The Android situation is this: there is no supported Android Glulx interpreter at this moment. But, as noted in a different thread (https://intfiction.org/t/suggestions-for-the-game-of-the-month-september-06/74/1), Ben Collins-Sussman has posted a work build of the bleeding-edge Twisty repository (bitbucket.org/sussman/twisty/downloads). It does not work for all Glulx games, but it seems to work for HL.
Well, uh
there is one interpreter for Windows Phone called “frotz.net” but it only plays z-code files and it seems to be rather buggy …
Greetings,
–MI
Everyone should know at this very second that HL is out and ready for purchasing.
A windows phone glulx terp could be culled together from fyrevm.
::drum roll finishes!::
Congratulations and hooray!
Current status:
HL can now be purchased through the iOS App Store and Itch.IO, but not through the Humble Store. The Humble people seem to have configured my page wrong. Will post when I know more.
(Also, I’ve sent out the Itch.IO download codes and some of the iOS gifts, but not the Humble download codes.)
All (working) links are on hadeanlands.com/ .
Okay, it’s all working now. All keys have been sent and you can buy the thing however you like.
Congrats! Can’t wait to have enough time to submerge myself into it 
I’ll also point out that performance has been A-OK so far on my gen 1 iPad, for anyone else who has one and was wondering about buying desktop vs. mobile. (It is SO NICE to have something new come out that works with it.)
Okay, so I didn’t realise that the game is in Glulx. But what, exactly, is preventing you releasing it as a standalone app on Android?
There is no supported Android Glulx interpreter, and I don’t know anything about Android development or the release process on the Google Play store.
Ah, I see. Not to worry, I’ve found a link that can help you: http://www.intfiction.org/forum/viewforum.php?f=33
Does anyone else find that, on the iPod, the font is just a tad too small to read comfortably and that if the maximum font size limit were increased playing would be a lesser visual strain?
EDIT - If someone does, I’ve realised that using the font Euphemia makes it better as it’s the biggest of the available fonts. FWIW.