| Cross-platform mobile application development and paymentsPosted on September 30, 2009 by Mikko OhtamaaFiled Under android, blackberry, html5, iphone, javascript, locationing, payment, series 60, symbian, technology We have been piloting multi-platform mobile application development and payments in few client projects. Target platforms usually include iPhone, Android, Blackberry and Nokia Series 60. Also there are two notable usual cases which need to be specially handled
Sounds easy, right? Well it isn’t… Below are some notes for our due diligence work which you fellow developers might find interesting. SDKsMobile phone vendors are jealously and don’t want to co-operate with each other. Building application which works in all handsets is major headache. We found some reasonable candidates for cross-platform mobile development doing HTML and Javascript. HTML and Javascript pages are converted to native application using a wrapper technology (a.k.a. appaccelerator). Doing Flash Lite or Java ME can be pretty much forgotten nowadays as they won’t run on the most hyped platform, iPhone. Flash Lite has poor support for anything except content authoring due to primitive and limited APIs. Java ME provides horrible user experience. (X)HTML is the only common language spoken by mobile phones. Thus, there has been a rise of “appaccelerators”, technologies which allow to create mobile applications with HTML(5) and Javascript.
All these wrap the browser component (WebKit) and provide some extra Javascript APIs when your web pages as executed under the application mode.
Rhomobile has little different use cases from the rest of the bunch as it provides client-side programming using Ruby and less focuses on Javascript/web applications. Payments and in-application purchasesThere are four major way to do mobile payments “inside” the application for bought content and subscriptions. The price tag on the application itself is left out on this discussion as the application stores themselves take care of it.
App Store payment is the most attractive as it provides the best end user experience. It allows you to use App Store payment mechanism inside the application. It is safe and no need to hassle with external payment providers. However, App Store payment can be used only for content consumed directly inside the application. You cannot use it e.g. for ordering a pizza. I think this might be related to recent EU legislation forbidding SMS payments for services not consumed in the phone itself. SMS payment is ok for little payments. Operators take big cut of the revenue, generally 30% – 70% depending on the country. Short code fees usually start from 500€ set-up fee + 500€ / month. SMS cannot be often send as a background, but the user is presented the normal SMS editor which reduces the user experience somehow. For credit card payments there exists several providers. Credit card has the cheapest entry fees, but the downside is that the user needs to have the credit card. This excludes teenager audience. Direct operator payments are not very well supported yet globally. Most western operators support them. The operator also takes a big share and the fixed fee is pretty high. My favorite payment provider thus far is Bango which provides credit card payment starting 9€ / mo. and scales up to worldwide SMS payments which cost few grannies per month. In most cases, the payment experience will not be smooth. You need to open the phone main browser on the payment provider page to do the payment. This usually will close your own application. Rarely you can do the payment inside the application and support multiple platforms. After doing the payment most platforms allow you to close the browse and reopen your application using a special URL handler. Wikipedia mobile payments page is also useful. Image upload<input type=”file”> won’t work on iPhone and some other platforms as those don’t have user browsable file system. Also the file dialog usually doens’t have image preview making it useless. Phonegap has a branch which supports images picking using iPhone’s own gallery browser. In any case, there is not yet cross-platform solution for this. Future prospectsIn some time-frame we will get rid of the need to wrap HTML applications natively as the web browser applications will support all HTML5 features without extensions and probably have some proprietary extensions for mobile specific features like SMS. We already have had some taste for this:
How to encode h264 video files for Nokia Series 60 standalone playbackPosted on September 23, 2008 by Mikko OhtamaaFiled Under linux, mobile, series 60, ubuntu Bored with Spiderman 3 which came with your Nokia N95 8 GB? This guide shortly tells how to get movies into your N95 on Ubuntu Linux using ffmpeg video encoder. The aim is to encode video suitable for playback from Nokia N-series (N95, N78, others) mobile phone memory card. We use h264 + AAC codecs which provides the best quality/compression rate for Nokia phones currently. Ubuntu does not distribute proprietary codes. First thing you need to do is to rebuild ffmpeg. Since Ubuntu 8.04 Hardy Heron ships with ffmpeg from 2007, which is aeons old in video codec years, you need to build libx264 and ffmpeg from SVN sources. Here are detailed, valid, instructions. Note that FFMPEG trunk is not currently stable (September 2008), so you need to use revision 15261 which needs this little patch. Indeed, this is a very difficult month to start your career in the dark world of video encoders. To make it legal and support open source codec development, please pay for your codecs. Then we use this guide by Robert Swain. We have a tiny sub 2,4″ screen, we do not care about the quality and do one pass encoding. By empirical research, I have found that the following MPEG-4 profile parameters are compatible with N95 8 GB and provide the optimal result. You can vary video and audio bitrate depending on your taste. Here is a script which recursivelu encodes all detected video files suitable for mobile format: #!/bin/sh
#
# Optimal movie encoding for Nokia N-series mobile phones
#
# Copyright 2008 Red Innovation Ltd.
#
# Say hi if you find this useful.
# We do some professional mobile video publishing, so if you
# need a helping hand please call us.
#
# Usage: Run encode.sh in any folder and all video files are recursively converted to mobile phone suitable format
#
# Note: We expect all the source material be in 16:9 aspect ration
#
# Also see http://www.nseries.com/index.html#l=support,search,faq,general,video%20encoding,53848
#
VIDEO_BITRATE=300k
AUDIO_BITRATE=72k
# Assume locally build ffmpeg + x264 in /usr/local/bin
# http://ubuntuforums.org/showthread.php?t=786095
export LD_LIBRARY_PATH=/usr/local/lib
# Search all source AVI, MPG and WMV video files
# Place all encoded files to the same folder with the source, with added .mp4 extension
find . -iname "*.avi" -or -iname "*.wmv" -or -iname "*.mpg" | while read src ; do
srcfile=`basename "$src"`
srcfolder=`dirname "$src"`
dstfile="$srcfolder"/"$srcfile".mp4
# The magical string!
# Size and cropping is for 16:9 source material, so that 320:240 display will have black bars.
# Fex pixels off... note that h264 sizes must be multiplies of 16, use 256x144 for streaming
# N95 RealMedia player does not seem to respect MPEG-4 embedded aspect ration info.
/usr/local/bin/ffmpeg -y -i "$srcfile" -acodec libfaac -ab $AUDIO_BITRATE -s 320x176 -aspect 16:9 -vcodec libx264 -b $VIDEO_BITRATE -qcomp 0.6 -qmin 16 -qmax 51 -qdiff 4 -flags +loop -cmp +chroma -subq 7 -refs 6 -g 250 -keyint_min 25 -rc_eq 'blurCplx^(1-qComp)' -sc_threshold 40 -me_range 12 -i_qfactor 0.71 -directpred 3 "$dstfile"
done
Introducing Python for Series 60 Community EditionPosted on September 1, 2008 by Mikko OhtamaaFiled Under mobile, python, series 60, symbian This blog post will introduce Python for Series 60 Community Edition. Pythor for Series 60 Community Edition is a new open source effort to push Python for high quality mobile phone development. It aims to provide a maintained software stack for creating real mobile applications. The codebase is derived from the original Nokia’s Python for Series 60 codebase, but has been refactored for better integration with third party extensions and patches and commercial grade application deployment. MotivationBuilding and distributionIt is difficult to distribute Python for Series 60 applications to the end user with the current Nokia’s PyS60 distribution. You probably want to modify or extend PyS60 in some way. Since the build chain and deployment model is not designed for changes this would collide with the other PyS60 installations. Symbian Platform security prevents installing conflicting binaries. Thus, one can effectively have one Nokia PyS60 application in the phone once. There are other problems: Nokia PyS60 distribution has UIDs in Nokia protected range. Embedded SIS file cause extra installation dialog and an application manager uninstall entry. Trimming down Nokia PyS60 distribution is a little bit difficult. To overcome all these issues we created a build chain which spits out monolithic PyS60 distributions. We build only one DLL whose name and UID can be decided. Also the build chain is Scons for Symbian, scrapping the obscure, inflexible and difficult to understand Symbian ABLD once for all. Evolution towards higher qualityCurrently there is no centralized authority to co-ordinate PyS60 open source developers and maintain the repository of all the extension and patches. This effectively prevents the biggest benefit of open source: open innovation and gradual evolution of the product. It would be very nice having all those third party extensions, now scattered around the internet, under one maintained source – making PyS60 more functional out of the box. The community maintained repositories do not have the same restrictions as ones managed by a big public corporations. It is not a probable target of a trigger happy lawyer action and ungentlemanly competition: the discussion and plans can be public and due dilugence check of the code more relax. We started the project in the Launchpad. Launchpad provide a distributed version control system (Bazaar) which streamlines the process of integrating third party commits and patches. This should encourage contribution. The standard build system makes it easy to roll out applications and extensions from bare C++ source up to the end user distributable SIS files. It is yet to see what kind of co-operation possibilities between the community and Nokia exists. In the future, it should be possible to cherry pick patches from PyS60 community edition to Nokia’s own version. Showing the commercial potential of PyS60 in the mobile application developmentOn Python you can write native Series 60 applications with very little effort compared to hardcore C++ banging, lowering the barries to enter the mobile application development. We do not deny that we have an extrinct motivation called money. Of course we have also instrict motivations like thinking Python is the best programming language in the world and we all want to be most respectable gurus in it. Gurus need to eat still, though. We hope that our effort does not go unnoticed in the mobile application development world and good subcontract offers fill our inboxes. Also, there is the John McClane effect. Unless we had done it, no one had. Somebody has to save the world, despite the hangover. It runs on LinuxSince we are no longer dependend on .BAT/Perl/Windows hindered ABLD buildchain, we can (almost) crosscompile and build native Symbian binaries in Linux and Python applications. All good hackers use Linux – but currently there are still kinks and you need to use WINE for some parts – all sane Symbian developers are tied to Windows based tools for now and so are these instructions. PrerequisitementsYou need all this stuff to get things running. Install BazaarYou need Bazaar distributed version control client. We are not planning to have fixed releases for Python for Series 60 community edition any time soon. This is because 1) the most magic happens at a compiler level and we are providing a buildchain 2) we hope this fosters incoming patches. Why Bazaar?
Install ActiveState PerlSeries 60 SDK has ActiveState as a prerequisitement for running its installer. http://www.activestate.com/Products/activeperl/index.mhtml Install Series 60 SDKUse only Series 60 3.0 maintenance release. Other releases have SDK bugs preventing correct Python compilation. Get the Windows installer from http://forum.nokia.com. Forum Nokia Registration is required. Please use the default installation location C:\Symbian\9.1\S603rd_MR. Install Carbide.c++ expressCarbide.c++ comes with a Windows compiler to compile the emulator binaries. You need this only if you indend to develop and test your applications on Series 60 emulator. http://www.forum.nokia.com/info/sw.nokia.com/id/dbb8841d-832c-43a6-be13-f78119a2b4cb.html Forum Nokia Registration is required. Use Software updater in Carbide.c++ to install PyDev, Python developer extensions for Eclipse. Install Python 2.5Scons build chain and our utility scripts use Python. http://www.python.org/download/releases/2.5.2/ Use the installer EXE and the default installation location C:\Python25. If you want to use advanced Bluetooth shell (PUTools) you also need wxPython and pyserial packages. Install SConsPython for Series 60 build script are based on SCons. It is a build system using Python as a recipe langauge. http://sourceforge.net/project/showfiles.php?group_id=30337 Install SubversionInstall Subversion client for Windows. This is needed for checking out Scons for Series 60. http://www.collab.net/downloads/subversion/ Registration to CollabNet is needed to download Windows binaries. Scons for Series 60SCons for Series 60 is available as a separate project. SCons for Symbian is a build toolchain intended as a replacement for Perl and MMP files used on regular Symbian projects. SCons for Symbian is not limited to build Python – You can use it to build any Series 60 C++ application. http://code.google.com/p/scons-for-symbian/ This is later checked out during to the environment construction, so you do not need to install it now. We have included a workaround for a problem with limited command line length on Windows. Included toolsThe following tools are included in the trunk tools folder: These tools are not licensed under Apache license. Some of them are under GPL license. However, we believe that distribution them is ok, since this falls under GPL’s mere aggregation clause. However if you indent to distribute commercial applications built from PyS60 Community codebase, make sure that you understand the set of different licenses involved. Set up build environmentEnsure that Bazaar is properly in your Windows path. Create a workspace folderFirst you need to subst (make a folder appear as a driver letter) in Windows. Open command line. Go to SDK folder. C:\Symbian\9.1>subst t: S60_3rd_MR T: mkdir workspace Now choose this folder as a workspace folder in Carbide C++ and create an Empty Symbian C++ project called ”pys60” there.
Checkout PyS60 community editionThe go to this folder T: cd workspace\pys60 bzr branch lp:pys60community cd pys60community\src Preparing the buildThis needs to be done only once. We need to pacth the existing Series 60 SDK headers which have some bugs. T: cd \epoc32\include \workspace\pys60\pys60community\src\tools\patch.exe -p1 < \workspace\pys60\pys60community\src\pys60-fix-3rded-sdk.diff EPOCROOT must be set for some Series 60 SDK tools to work. We point to T: drive root. T: cd workspace\pys60\src set EPOCROOT=\ As we still have some dependencies to the legacy system, one needs to configure the build system using PyS60 setup. This will generate some files and defines for Series 60 versio 3.0. c:\Python25\python.exe setup.py configure 30 Do not run bldmake bldfiles. You need to convert legacy MMP build files to SCons based. First we need to possibly fix up PATH, since Carbide C++ might break it. set PATH=c:\program files\bazaar;c:\program files\CSL Arm Toolchain\arm-none-symbian elf\bin;c:\program files\CSL Arm Toolchain\libexec\gcc\arm-none-symbianelf\3.4.3;C:\program files\CSL Arm Toolchain\bin;t:\epoc32\gcc\bin;t:\epoc32\tools;t:\epo c32\tools;C:\program files\CSL Arm Toolchain\bin;C:\Program Files\Common Files\Symbian\Tools;C:\Perl\site\bin;C:\Perl\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem c:\Python25\python tools\mmp2scons.py ext\\calendar\\calendar.mmp:60:7: warning: no newline at end of file Creating recipe ext\miso\build.py Creating recipe ext\socket\build.py ... Done! Checkout SCons for Symbian. We assume it lives in src tree. "c:\Program Files\CollabNet Subversion"\svn checkout http://scons-for-symbian.googlecode.com/svn/trunk/ scons_symbian Running the buildNow we can execute the actual Python build script. This will create one monolithic emulator DLL which has almost all the PyS60 extensions built in – some extensions need manual building, since they rely on headers not found from standard Series 60 SDK. You might need to reset PATH to default to Carbide C++ after the previous mmp2cons step by reopening the console window. c:\Python25\Scripts\scons You should see the following output. As you can see, UIDs are being allocated dynamically as instructed in Scontruct UID_BASE argument. scons: Reading SConscript files ... EPOCROOT=\ Info: SIS creation disabled Building winscw udeb Defines [] Getting dependencies for e32socket.pyd Getting dependencies for _topwindow.pyd Getting dependencies for zlib.pyd Getting dependencies for _locationacq.pyd Getting dependencies for _location.pyd Getting dependencies for _graphics.pyd Getting dependencies for _sysinfo.pyd Getting dependencies for Python222Config.lib Getting dependencies for Python222.dll Getting dependencies for Python_appui.dll Allocated UID:0xE1000000 Getting dependencies for Python.exe Allocated UID:0xE1000001 Getting dependencies for Python_launcher.exe Allocated UID:0xE1000002 scons: done reading SConscript files. scons: Building targets ... ... scons: done building targets. Now you should be able to start a custom built Python shell in the emulator. You should see the following applications in Installation menu: helloworld, btconsole and filebrowser. Try launch helloworld and if it opens a pop up dialog the build has been succesful. Building a SIS file for mobile phonesTo build a target distribution type: scons release=urel compiler=gcce dosis=true This should yield to the result: scons: Building targets ... ensymble(["MyPythonForSymbian.sis"], []) scons: warning: no package version given, using 1.0.0 scons: warning: no certificate given, using insecure built-in one scons: done building targets. If you want to build a SIS file signed with your developer certificate: c:\python25\scripts\scons compiler=gcce release=urel dosis=true simplesis={'--privkey':'C:\\Certificates\\PrivateKeyNoPassphrase.pem','--cert':'C:\\Certificates\\MyApp.cer','--passphrase':''}
For now, installing the SIS file works only for C drive – we’ll fix this little issue soon. If you do not have a symbiansigned.com developer certificate you can sign the SIS file online for one phone (one IMEI code).
Building your own applicationThe purpose of this project is to make rolling out your PyS60 applications possible – so here we go. Currently we make a quite bad assumption that all the application live in the same source tree with PyS60 community edition due to problems with absolute file paths with Symbian build tools – we will figure out a long term solution for this later. PyS60 applications are stub Symbian executables which boostrap Python virtual machine and start the Python code execution. Executables are linked against a custom PyS60 DLL and they are restricted by capabilities given to the EXE file. PyS60 applications live in applications source tree. The source tree comes with Bluetooth console, Hello world and File browser sample applications. Scons build scripts takes as applications parameter a comma separated list which applications are included in the build. scons builtin=all applications=helloworld,filebrowser Applications consist of
See applications\helloworld folder to examine what files are needed to build an application. All application Python modules go to the private application folder (/private/myapplicationuid). Default.py must boostrap PYTHONPATH (sys.path) for this folder – PYTHONPATH defines where Python interpreter looks for the code. Application UIDs can be chosen manually or they are picked automatically by Scons for the unprotected test range. Note that Python Script Shell application is handled out of this flow due to its legacy heritage. Adding in your own extensionIf you have development an PyS60 extension you can drop in into the buildchain easily. Each extension is defined in ext subfolder. It consists of necessary CPP, H and Python files. The building structure is defined in build.py using SConstruct command PyS60Extension(). Build.py files can be automatically generated from legacy code using mmp2scons.py converter.
c:\Python25\python.exe tools\mmp2scons.py ext\calendar\calendar.mmp:60:7: warning: no newline at end of file ext\progressnotes\progressnotes.mmp:38:7: warning: no newline at end of file ext\uikludges\uikludges.mmp:37:7: warning: no newline at end of file Creating recipe ext\\socket\build.py Creating recipe ext\\glcanvas\build.py Creating recipe ext\\graphics\build.py ... ...Done!
c:\Python25\scripts\scons
>> import applicationmanager If your extension is using thread local storage (Dll::Tls()) you might need to figure out how to workaround with it. See socket module for example. You may also need to play around with the init function of the Python extension – it must be init + module name. Developing on targetIf you want to develop your application on a mobile phone, you do not need to go through the full development cycle for every little change. It is possible to update Python files on a phone without SIS installation. You can either automatically synchronize changed files from your PC to Phone (the example below) or you can edit files in-place on the Phone either using PCSuite or Series 60 SMB server. Here are short instructions how to update files using PUTools console (btconsole). PUTools is wxPython based remote Python shell which allows you to run Python console commands over a Bluetooth connection from your PC. PUTools also has a file syncrhonization feature – after editing source code on the PC changes are reflected automatically to the phone.
T:\workspace\pys60\pys60community\src\tools\putools\pcfiles>c:\python25\python.exe putools.py com5 >> import filebrowser >> filebrowser.FileBrowser.run() Release notesHere is the short summary of differences with the current PyS60 community edition and one available from Nokia. This information is also available in divergence.txt file in the source folder. 2008-08-29 Mikko Ohtamaa <mikko@redinnovation.com>
* PyS60 general
New build chain and static config generation
Migration tool for MMP -> Scons based extensions
Added several tools included in the core distribution: sisinfo, ensymble, cog, patch
Patched py2sis tool
Contains extension: applicationmanager
Contains extension: uikludges
Contains extension: progressnotes
Contains extension: miso
Contains application: Bluetooth shell
Contains example applications: filebrowser, helloworld
Changed Bluetooth console bootstrap to e:\startup.py
2008-08-15 Antti Haapala <antti@redinnovation.com>
* e32socketmodule.cpp:
socket.access_points has more information, two new
fields is given per access point: isptype and bearertype,
whose values are integers corresponding to values returned
by CApSelect::Type and CApSelect::BearerType respectively.
No symbolic constants are yet exported.
* appuifwmodule.cpp:
multi_select_list has a new argument, selected, which defaults
to None. Given a list of integers, the items with the given indices
are initially selected.
ConclusionWe hope this helps you to get started with PyS60 community edition. It’s still a bit complicated, since setting up the build environment on Windows is a such a pain. In the future, when the Linux based build system is reading settings up the development environment should be easier – all those boring steps happen automatically. This might be still too difficult for some of the readers, since a lot of prerequirement work must be done before anything useful can be done. Feel free to comment the article in this blog, but we hope that you use Answers section in Launchpad to ask help and technical questions related to PyS60 community edition. PyS60 application release build toolchainPosted on April 19, 2008 by Mikko OhtamaaFiled Under mobile, pys60, python, series 60, symbian A common question for Python for Series 60 newcomers is how to build standalone Symbian applications from Python source code. We have been using Makefile based toolchain internally. I describe it in this picture, I didn’t bother to add thumbnail for the image, since it’s a 3400 pixels wide diagram. The diagram describes building a PyS60 application with some Python extensions (Symbian native C++) mixed in and bundling it all to one downloadable SIS file. The application will appear as any first class S60 application in the menu and the user does not know it’s running Python internally, besides bad installation experience (it challenges Microsoft installers with all those unnecessary yes/no questions), extra uninstaller entries and slow start-up time. The biggest problems are caused by embedded SISs (SIS inside other SIS files) which are not treaded very wel by several Symbian parties. In theory, it could be build one monolithic SIS, but you’d need to recompile PyS60 from scratch and patch UIDs inside it for your own UIDs received from symbiansigned.com. We are planning to explore SCons based build solution to address this problem, since Makefiles are a bit unflexible with tasks like PKG file and UID range generation. Here is a PKG file example for final user distributable SIS file. Also, see UIKludges project for additional details for PKG files of Python extensions. You need to have
You need to master
Pros
Cons
Ps. I would have put this thing to wiki.opensource.nokia.com, but their webmaster email address is non-functional and one cannot upload images to their Wiki. |
