If you are set on using just the native iOS UI tools this solution probably won't work, But I maintain a cordova plugin for libpd, you can find it here: https://github.com/robertesler/cordova-pd. There are instructions on how to use it on the README page. With cordova you can use HTML5/Javascript for your UI and interface with a Pd patch. Cordova will allow you to create an iOS platform which generates an Xcode project.
Otherwise, the examples on the pd-for-ios still 'should' work. I haven't tested all of them for at least a year, but that is also worth a shot if you really need to use native iOS UI tools.
Good luck!

Getting 3rd party externals with libpd on iOS is not that straight forward. Because iOS doesn't allow dynamically linked libraries, you have to statically link them. So you have to include all of the source code for each external in your Xcode project and then called their external_setup() function in the ApplicationDelegate.m or somewhere in your code. You can see more about this here: https://github.com/libpd/pd-for-ios/wiki/ios
As for abstractions like out~.pd, those can be put with your patch in the Resources, or sub folders and use the [declare] object. They work as expected since they are just text files.
This doesn't mean the externals will work as expected, they may have bugs or other issues on the iPhone chips (arm64), or have other issues when actually running on a device.

Hi @mcbublick. Are you using the examples included in the repo? Are you testing on a device or emulator?
That message means that the externals were probably not included with the application. So there may be a step missing in the Android project.
Is it just one external that is not created, or is it multiple? If so which ones?
You could also use the Android Studio APK Analyzer to look at the .apk file and see if there is a /lib folder with all the proper dynamic libraries like libpd.so, libbob.so, libpique.so, etc.
I haven't tried the repo examples in a long time so I can't say whether they still work or not.

Hi @sadielcuentas,
I don't know if there are alsa drivers for ARM architectures, but the Linux kernel used by Andronix won't be able to use them anyway. You have to install the Ubuntu Studio audio package: sudo apt-get install ubuntustudio-audio
After that in Pure Data choose "portaudio" in the Media menu. It should default to pulseaudio. Also make sure you have started pulseaudio in the terminal before starting Ubuntu: pulseaudio --start
This version of Linux is very limited with which audio software you can use, anything that relies on Jack or ALSA won't work. So no Audacity or Ardour. But I have gotten Pd, Cecilia, LMMS, REAPER and Processing working so far, among others.

I don't know if you figured this out or not. For me Pd-l20rk was not on the MacOS list of applications with permission to access the microphone. Pd-l20rk did not prompt for microphone access for whatever reason. Since I'm on a university machine, my only choice was to open Pd-l2ork via the command line. This worked but now the only way to ensure microphone permissions is to open it via Terminal.
I put the direct path to the executable in the command line:

/Applications/Pd-L2Ork.app/Contents/MacOS/nwjs

@sadielcuentas I don't know if you figured this out yet. I was able to get Pd to work using Andronix with Ubuntu 20.0.4. At first it didn't work as you documented. However, after I ended up installing ubuntustudio-audio it ended up working.
I had to choose "portaudio" in the Media menu then it saw pulse audio as the output. I can only get sound out at the moment. I don't know if input is even an option but at least it works somewhat.
I hope this helps someone.