The Day of Sagittarius III for iOS was finally preserved, and uploaded to the Internet Archive.
https://archive.org/details/the-day-of-sagittarius-iii-1.02-i-os-3.0
I wonder why Kadokawa never ported it to Windows as a freebie with some of the light novel volumes.

Oh shit, i thought this was gone forever. Thanks OP.

>>714844249
You're welcome.

>>714841798 (OP)
What exactly is this? I'm not very well versed in Haruhi spin-off content.

>>714845260
A defictionalisation of the game featured in The Day of Sagittarius (episode 11 of the first season, and episode 27 in the chronological order).
Within the series, this game was created by the computer club (which Haruhi blackmailed for a new computer) and they challenge the SOS Brigade to play it, and defeat them.
The real game was released in 2010, and was delisted when 32-bit support for iOS died. It was never released on Android, nor Windows.
Thus, it was lost for many, many years. Not anymore, though.

>>714845562
Oohh, a real version of that game they play. I forgot it was named that. Good shit.