This thread has shown me that there is a lot of incomplete options, but many more than I would have suspected.

Thanks for the very kind words, but a shudder goes down my spine every time I hear someone has looked at my orrery code! I consider it to be a mess - very poor (actually, almost no) separation of the UI code from the calculations code, for example. There is also stuff in there that was intended to make performance tolerable for Openmoko phones, which does not make sense for more modern devices and should be stripped out.

Regarding your real question, I guess I've been both lazy and poorly informed. For example, I thought that Wayland would provide the sort of effortless X11 compatibility one gets on Mac OS X. It looks like that is not the case. The thing I personally need *most* is X11 server mode on my handheld, displaying for a remote client. It doesn't look to me like that's available either with SailfishOS or Ubuntu Touch. For those OSs it looks like X11 capability, at best, supports local X11 clients. And there are these little caveats like "input doesn't work", etc., which make a big difference to me. Using VNC is much more cumbersome than having a real X11 server, and some of the remote machines I work with are headless.

I guess my best course is to wait for Pyra. If both my n900s (and any neo900 that I get my hands on) die before Pyras ship, my best course might then be to try to get SailfishOS running on a Nexus 5 (or whatever is the best "supported" hardware at that time) and try to strip out Wayland and substitute X11.

The fragmentation of Linux display managers into X11, Surfaceflinger, Wayland and Mir is certainly a grim development. I know X11 is full of ancient cruft and providing full X11 server compatibility involves supporting crazy things like its old, ugly pixel fonts, but given Android's huge market share, I think Jolla and Ubuntu should have just gone with Surfaceflinger.

The real irony is that if Apple were to implement the X11 capability in iOS that they provide in Mac OS X, my best choice for managing remote Linux servers would be an iPhone!

That is ironic but very interesting.

Apple haven't provided X11 support in OSX for some time now. The last X11.app was OSX 10.7.

It's now a separate open source project as XQuartz of which Apple do contribute to but it's pretty clear they don't think it's that important. There's no support for retina displays for instance.

The chances of them ever supporting iOS would be approaching zero.

IME it's never been that great on OSX even when they did support it fully. It was more of a hangover from NeXT.

Is this related to them dropping OpenGL? I've just started learning about it and was quite surprised to read that they don't support the newer OpenGL standards. Shame, because otherwise Qt + OpenGL would be a great way to develop apps that run nicely on all 3 platforms.

I certainly didn't seriously think Apple would ever bring X11 support to iOS. I was just pointing out how ironic it is that X11-compatibility "just works" in Mac OS X, while X11 works poorly at best (after additional software is loaded, and scripts are written) under Wayland or Mir, despite official claims that these display managers would provide X11 compatibility.

I was unaware Mac OS X did not support X11 on retina displays. I'd better take care of my ageing Macbook!

I don't think it's related. They dropped X11 much earlier.

They'd rather you used Metal. It's available on iOS and OSX and although there's often significant performance reasons to use it over OpenGL, the upshot is you're then developing to an Apple only API and not supporting Android.

XQuartz pixel doubles rather than take advantage of the higher dpi. ie. it works but next to a Mac app on the same screen it looks like blurry bitmapped crap.

edit: I only know this because last week I needed the statistics package 'R' which is an X11 app on the Mac. I then realised I'd not installed X11 on my Mac since I bought it in 2012. I've used CDs more often.

I still dont see why (the lowest common denominator)
running a "headless" X11 server running on your phone with a VNC display driver and a VNC input driver [which you locally connect to via a vnc client] shouldnot work.
It is not x11 or vnc it is: X11 via vnc.
Sure it is a overhead going through kind of framebuffer driver and local network but the VNC "last mile" gives you also input and display translation [from touchscreen to rightmouse click (+) drag and drop, zooming] which are sometimes needed for non fingerfriendly X11 applications.
[Or can you rebind the rightclick drag and drop gesture to shift + drag and drop on any open gui toolkit? Im hoping for emacs2020.]

This is done on https://www.youtube.com/watch?v=XfMLzlki9XE but the connection vnc server to vnc client is over wifi and not locally.
[But it shouldnt be laggy anyway, except he has a very very very bad wifi connection]

https://www.phoronix.com/scan.php?pa...hone-XMir-Apps

Vnc to X on chroot on modern android devices isn't laggy at all. And, as I reported previously, X is available too without the need of vnc.