qw The Game ported to Android

I decided it's time to port qw The Game to Android, as a way to see how the publisher story works on Google Play compared to Ovi Publish and also to see how mature the Qt port to Android is.

For my port, I used Necessitas alpha 3 update 4, which you can download from the project website. Necessitas already includes both the Android SDK (that's the SDK you use in general, and contains all the Java APIs, etc..) and the Android NDK (that's used if you want to do native C/C++ development), so no need to install anything else. You can start Necessitas Qt Creator using "QtCreator/bin/qtcreator" in the Necessitas installation directory, but Necessitas also creates a launcher icon if you shy away from command lines.

The assumption is now that you have an existing Qt project with a qmake project file (.pro). Just open that .pro file in Necessitas Qt Creator and let it create the Android scaffolding. You can now try to build the project and run it - either in the Android emulator, an actual Android device or your N900, N950 or N9 running Nitdroid (the N950/N9 port is actually quite nice these days, and can be installed alongside Harmattan by flashing an open mode kernel with Android patches, replacing some init files and placing the Nitdroid rootfs inside /home/nitdroid/).

When you first start a Qt-based application on Android, it will redirect you to Google Play to download Ministro, which will take care of downloading the Qt libraries and storing them in a central, shared place, so that all Qt-based apps can use the same Qt libraries (which means that you can do closed-source apps, because they are dynamically linked to the LGPL'd Qt, and it also means that apps are smaller, because Qt doesn't need to be shipped with each app). One disadvantage is that the end user experience is not seamless on first startup, because your users will have to install Ministro first and wait for the Qt libraries to download.

Anyway, now you got that far and got your application running - or not. If you are missing libraries, and your application doesn't start, open the "Projects" tab in Necessitas Qt Creator and click on the "Run" tab for the Android target. There, open "Package configurations" and click on "Libraries" and check all Qt libraries that you need. When you compiled your application, there's a button ("Read information from application") that will analyze your binary and check the right Qt libraries. You can also add "Prebundled libraries", which are dynamically-linked shared libraries that will be shipped with your application. You can also check out the "Manifest", "Application" and "Permissions" tabs and configure it to your liking.

Protip: You can build the Android package on the command line using "ant" as soon as you have used Necessitas Qt Creator to create the initial scaffolding. The "android" folder will be created inside the folder where your .pro is located, and there you will find a build.xml.

Now to some code-level customizations that I had to do for my game, qw:

• QtMultimediaKit was not found - I had to comment out sound effects for now
• Automatic screen rotation - My game is landscape-only, and I had to tell the Android system in the AndroidManifest.xml file
• Qt.labs.particles was not found - Again, I simply commented it out for now; I guess these QML plugins should be easy to add to Necessitas, but I didn't bother to find out for this first try
• Screen resolutions! - Don't assume 800x480 (in case of the N900) or 854x480 (in case of the N950 and N9); make your app scale properly to the screen resolution at hand. Test this by creating a non-fullscreen window on your Desktop in different sizes, and see if the content looks right. For a quick'n'dirty first try, use QGraphicsView::scale

As far as the publishing experience goes: You have to pay a one-time fee of $25 to be allowed to publish to the Play Store (compare this to a one-time fee of 1 Euro for Ovi Publish and a yearly fee of $99 for the iOS App Store). What I found interesting is that there's basically no QA (apart from automated checks that are very helpful and give guiding error messages) and an application uploaded is published in a matter of minutes. I also like the fact that you can add a YouTube video link to the Play Store submission, so users can get a preview of how the experience is like. I published the app for free, and the UI warned me that it's not possible to convert a free app into a paid one in the future, which doesn't matter for me, but it might be a useful hint for other publishers.

qw The game is now available on Google Play for free. It's also available in Nokia store for free. Go play!

Comparing Mobile OS SDK availability by platform

Coming back from Nokia World in London earlier this week (thanks to Nokia Developer for inviting me), I've been thinking about the SDK availability for different mobile operating systems given a specific Desktop platform. While leaving out all the other criteria (openness, libreness, licensing, UX, device capabilities, programming languages, toolkits, data formats, annual costs for the SDK/developer account, store rules, target audience, revenue splitting, advertising/in-app purchase options, coolness, etc..) developers can choose their mobile OS by, I want to highlight a specific aspect: The availability of an SDK for a given Desktop operating system.

First up, I'm only talking about native apps here (with "native" being anything that's not just some HTML+JS zipped up or served via the web, i.e. native usually means you need to have some form of compiler, even if it targets a VM). If you are into "web apps", chances are that you don't need an SDK to get started (even though one might help). I'll look at iOS and Android (because these are the strong mainstream OSes today), Maemo/MeeGo (because it's my platform of choice right now), Symbian (because I'm targeting it too with Qt) and WP7 (because that's what MS and Nokia want to succeed). When I write "MeeGo" I mean MeeGo 1.2 Harmattan, which technically is more like a "Maemo 6". Think "the OS that the N9 runs". I have a bit of experience with Android development, no experience at all with iOS or WP7, some experience with Symbian (through Qt) and arguably lots of experience with Maemo/MeeGo (yay!).

Why is that important? First up, if you are a Linux or OS X user, chances are that you don't have a Windows installation, and installing Windows will cost you money (for the Windows license), time (because you have to set it up) and space (because you have to dedicate a partition/VM image for it). If you don't have Apple hardware, getting an OS X installation means purchasing Apple hardware (ignoring Hackintoshes here), which is again costly. At least you would need to purchase OS X and dedicate a partition/VM for it, plus the time it needs to set it up.

Why OS X and Windows? As far as I know, if you want to develop for iOS, you have to use XCode, and that is only available on Mac OS X. Similarly, if you want to develop for WP7, you have to use the Windows Phone SDK, which is only available on Windows (>= Vista according to the website, so your XP install might not help there).

Now, let's look at Android, MeeGo and Symbian. Android's SDK is available for Windows, Linux (x86 and amd64) and Mac OS X. You can compile your apps on all these platforms (using your system's javac + tooling provided by the SDK). For C/C++ Android apps, the NDK is also available for all three platforms. For Qt-based OSes (Symbian and Maemo/MeeGo), the Qt SDK itself is available for Windows, Linux (x86 and amd64) and Mac OS X (64-bit). Using the Remote Compiler (which uses compilers set up on a server farm at Nokia, and you need a Nokia Developer account to use it) you can compile Symbian binaries on OS X, Linux and Windows, although the locally-installable compilers for Symbian are only available on Windows (at least that was the case 6 months ago). For Maemo and MeeGo, cross-compilers exist natively for all supported platforms of the Qt SDK, so without using Remote Compiler, you can build and package your Qt apps for MeeGo on Windows, Linux (x86 and amd64) and OS X.

Now, people can argue that one can set up dual-boot or virtual machines to support all OSes, but that's not the point. The point is that if the SDK is available on all Desktop platforms (note that this is not the same as SDK targetting all mobile platforms), developers can retain their choice of Desktop OS on which they develop on, and are not forced to use OS X or Windows for development of apps for the corresponding mobile platform (I also understand the reason why these companies only provide the SDK for their own Desktop platform, but that is not a good reason from a developer's point of view).

I hope that the Qt SDK will continue to support Windows, Mac OS and Linux for any mobile target platforms that it supports - be it ones named after winds or not - so developers have a choice of development platform.

In other news, gPodder 2.950.15 has been uploaded to Nokia Store (still waiting in QA) which fixes video playback and streaming, so grab the update on your N950/N9 when it becomes available :)

New gPodder versions for your N8x0 and N9x0

It's been over two months since I've released a new stable release of gPodder. Now it's time again to catch up with some of the fixes that have landed in the "master" branch of gPodder (while we are still adding cool stuff to the "tres" branch, where the QML UI and other improvements happen). Anyway, gPodder 2.16 "Over There" should be available in Maemo Extras for both Diablo and Fremantle soon, please test the package and (in case of Fremantle / Maemo 5) also vote for it, so it can land in Extras eventually.

For the Nokia N950 (and also for the N9), there's already a very early alpha build of the QML for you to try - please note that you might have to remove your database and downloads to be compatible with any changes when the final version is out. There's a thread on forum.meego.com with instructions on how to get it and a screenshot - please also use this forum thread for feedback and any questions that you may have.

In related Maemo/MeeGo news, That Rabbit Game has been packaged for MeeGo Tablet and should be available in AppUp already. There's also a pure OpenGL ES port for webOS, although it's missing some features of the Qt version. If you haven't been following gaming news, our multi-touch game Mong (which is going to have its new name "Plonk" soon) is available for MeeGo tablets and I'll have a Harmattan package for you to try really soon! There is also the Harmattan Event Feed Library for Python which should make posting data to the event feed awesome. And if you really want to port your PySide apps to Android, try PySide for Android, which has just been released today. Yes, lots of stuff happening - expect more in the coming days/weeks :)