When I started using Ubuntu Touch, I started developing a document scanner app called Camera Scanner out of curiosity. It turned out I am much more interested into the tooling than app development itself. Many features I contributed to Clickable were inspired by my work on this app while the Camera Scanner only made some progress thanks to contributions from friends (Stefan, Krille, Cibersheep). It reached a state where it kind of works, but not very reliably and with little feedback to the user, making the user experience rather frustrating.

I would love if somebody would be motivated to put love into the Camera Scanner App to make it the great app it could be. If someone would want to "only" take care of the frontend, I'd still be available to put some more work into the backend.

The backend is mostly a C++ reimplementation of the Open Note Scanner backend (written in Java), but less configurable (yet). It makes use of OpenCV for image processing.

For app developers:

• Update to Clickable 8.3.1
• Set the framework to ubuntu-touch-24.04-1.x (currently ubuntu-touch-next-internal points to 24.04, too)
• Set the app armor policy to 2404.1 (not 9999 anymore).

I think the biggest hassle in the short run is neither packaging nor the store, but the QML framework and System Integration. It is not too hard to have different packaging configurations in your repo and deploy to different stores.

Pure Maps by @rinigus is a great example on how platform independent mobile linux apps can be done. The most interesting part is the platform abstraction in QML, in my opinion. The app assumes some QML files in a folder called platform, which is just an imaginary interface to Elements like a Button, a Dialog, Clipboard or file chooser (aka Content Hub in UT). Adding support to another platform means to create a new platform folder and implement the interface using the specific platform frameworks stuff. The packager then just links the desired platform folder to platform and builds the app.

Now you may wonder whether it is necessary for each and every app developer to implement each platform support over and over again. And of course it is not. That could be done in one place shared by all apps. Someone has already started that meta-framework-project as a spin-off from Pure Maps, which just needs to be explored and picked up by app developers.

Sure, this won't solve all problems like (push) notification and background services. But it should help a majority of all apps to become available on many platforms.

It still works well on Ubuntu Touch. I added a clickable.json and changed the framework to 16.04: https://gitlab.com/jonnius/scriptor
If someone is interested in maintaining the app, please just fork the repo and release it to the OpenStore. The README needs to be cleaned up and the busybox download in app does not seem to work. But I don't think it is even necessary, so maybe it could just be removed.

• There is a brain dump by Marius, where he started with Raspbian.
• There are official Ubuntu Core images
• There are some unofficial Ubuntu server images
• There is also Ubuntu Mate 16.04 for Raspberry Pi

What would be the best to start with?

I didn't touch the README. You downloaded the old 15.04 version. Please build the app for 16.04 using Clickable instead. I don't plan to maintain the app, just wanted to show it is still mostly functional, in case anyone wants to pick it up.

Marius mentioned he documented how to build the Lomiri stack in the last Q&A. Are those notes available somewhere already?

As far as I see Snappy Ubuntu Core has a very similar approach to Ubuntu Touch with a read-only filesystem and there is an official download for the Raspberry Pi. I wonder how this could be interesting for us? Could'nt it even be a good base for Ubuntu Touch at all, assuming we'd want to switch from click to snap packages, if that would be necessary then.

Fluffy Chat Flutter is the cross-platform version of Fluffy Chat, providing full E2E support and being actively developed. The QML version of Fluffy Chat will only be maintained on a low level until Fluffy Chat Flutter works on Ubuntu Touch as well (requiring Wayland support afaik), which will make the QML version completely obsolete.

Unfortunately the QML version we have at the moment does not support E2E. As the airport in Berlin is coming close to be opened, we want to provide you with a temporary solution: Pantalaimon.

Pantalaimon is provided by the Matrix Foundation and described as:

Pantalaimon is an end-to-end encryption aware Matrix reverse proxy daemon. Pantalaimon acts as a good man in the middle that handles the encryption for you.

Messages are transparently encrypted and decrypted for clients inside of pantalaimon.

You can find instructions as well as possible next steps in my repository. Feel free to test, provide feedback and jump in to improve it.

Update: Source code and releases: https://sr.ht/~thrrgilag/pantalaimon-ut/

You got the right approach already. Clickable does not require any specific project structure. Ideally you would just add a clickable config (clickable.json) and a few UT specific files (manifest, apparmor config, maybe a specific desktop file), see Pure Maps for example. Only the folder packaging/click is UT specific.

I would go step by step like this:

• add a simple clickable.json with builder set to qmake
• run clickable build -a amd64 and see what happens
  • you might need to set some build_args that would be consumed by QMake
  • you will probably need to add dependencies to the build container (dependencies_target and dependencies_host for build tools)
  • for dependencies that are not available in the ubuntu repos, you already mentioned the libraries feature. Refer to this guide for details
• Once it builds the app, you can start with what is needed for the click package
  • Create a new app with clickable create filling in the details
  • Copy over the manifest.json.in, rename it to manifest.json and just put fix values where there are placeholders.
  • Copy over the the apparmor file and add policies if needed.
  • For the desktop file I would look for one in the build or source dir, copy it over and add the line X-Ubuntu-Touch=true.
  • Add those 3 files to install_data.
  • Try first in Desktop Mode with clickable desktop and then on the device clickable chain build install launch logs -a arm64 # or armhf

Just for calification: click is the package format that Ubuntu Touch expects. The tool to create such a package is called click, too (but you don't use that one directly if using Clickable). Clickable is a tool that knows how to handle click, do cross compiling utilizing docker (Clickable also provides the necessary images), handle build tools like CMake, QMake or cargo, run apps in Desktop Mode, handle some debugging tools like gdb, configure an IDE, install a click on your device and so on. So it is like a swizz knife for UT app development...

For app developers:

• Update to Clickable 8.3.1
• Set the framework to ubuntu-touch-24.04-1.x (currently ubuntu-touch-next-internal points to 24.04, too)
• Set the app armor policy to 2404.1 (not 9999 anymore).

They grow up so quickly...

@talkless please clean the build dir when switching between versions.

@rondarius that is so cool!

@talkless the latest version of Pure Maps is UT 20.04 only. If you run 16.04, you can go back to Pure Maps 3.1.1 which is still made for 16.04.

@talkless you might need to build clean once, looks like an outdated build cache.

@chester could you please paste the exact error message you are referring to? Btw, if you struggle pushing the SSH key via ADB, you can use other means like MTP or sharing it via a messenger.

OSM Scout Server 3.0.0 is on its way to the Open Store, still waiting for manual review, because it is unconfined. After updating to version 3.0.0 it is required to restart the system once and let the app update its maps. The apps have already been made available for download as the app update was rolled out on other platforms yesterday.

To my understanding, the old version of the app should not have downloaded the new maps. Apparently it did. Sorry for the inconvenience.

The problem is make: 'install' is up to date. when this isn't true. You can avoid it by always building picotts clean. Or by touching the binary as in https://github.com/rinigus/pure-maps/pull/646. Just be aware that the master branch of Pure Maps is already configured to build for UT 20.04.

What is also missing is updating the app armor policy to 20.04 and renaming the X-Ubuntu keys in the desktop file to X-Lomiri.