HTML5 apps: how to make Javascript faster? - html

I'm trying to make a HTML5 word-game that should eventually be wrapped into an app for Android and iOS.
For now, I only tried Phonegap / Cordova to build the app, but it is VERY slow on my 2-year old Android 2.3.3 phone. Operations (like indexing the dictionary file or finding all words that start with a certain prefix) that take only 100ms in Chrome on my desktop, take up to 2 SECONDS on my phone. I know this is because Phonegap uses the Android Browser, which is very slow on 2.3.3.
So, what are my options now? I want this app to be able to run smoothly on Android 2.3.3.
I read about CocoonJS, Trigger.io and appMobi (now Intel SDK).
I know these techniques can improve canvas performance, but will they let my Javascript run faster too ?
Maybe there are other solutions that really compile the Javascript into native code?
Or some HTML5 wrapper that I'm unaware of that includes a version of Chromium instead of using the Android Browser?

With CocoonJS your app will run under a optimized engine so your app will run significantly faster, still they recommend some Javascript good practises for performance optimizing that you should take care of them. The point is to help JavaScript compiler following some coding rules.
Here you have some slides done by #mortimergoro of the engineering team of Ludei that explain the behavior of JavaScript compiler:
http://goo.gl/0RdhIY

Related

Adobe Flash Builder

Is there any way which can be adopted, to create cross platform responsive mobile apps using Flash Builder ?
We are using our custom written Resigning Engine for this purpose right now, but we tend to replace it with any generic Resigning tool or to cater responsiveness for all kind of devices/platforms.
Being on the same cross platform development, i.e. Flex, Action Script and MXML, is there any solution for this?
Thanks
It's possible deploy Flex-apps on Mobile devices, see Mobile app development
at Adobe Devnet more details
You definitely can develop Android and iOS apps using Adobe Air, Flex, AS3, MXML and publish them on Apple App Store and Google Play Store. But it's limited to these platforms, and Adobe is very unlikely to add any new platform to this list.
Pros:
it's really cross-platform. Once your application works on one, it's really easy to get it working on the other; so the development cost compared to native applications is much lower;
you may have some OS specific features/design; using by example OS specific CSS directives;
You perfectly may create an app with a responsive design, all tools are provided, but like for HTML/CSS, it requires a lot of work;
you may access all phone features (sensors, camera, etc...) using Adobe Native Extensions
Cons:
the size of the generated application: as it includes the AIR runtime, even a very simple app will weight around 12 Mb (9 for the runtime + 2.5 for Flex);
the performances are correct but not as good as those of native apps; one of the reasons is that Flex does not allow to use GPU for rendering (but Flex is not a framework for creating games);
it would be costly to get an app looking like a native one, as you would have to mimic all of native components. There was a project to do this (Eskimo), but it looks dead, and the components were not polished enough to be used in production when they stopped the development;
Adobe Native Extensions offer is rather limited, and they are quite tricky to write; (these drawbacks are not strong ones: you can write extensions, assuming you know to write native code; and most of the common features are available as ANE);
like with any other cross-platform technology, there are a few issues that you can't fix by yourself; you just can wait for Adobe to fix them when it's a problem in the compiler or the AIR runtime; hopefully they follow a 3 months release cycle since they launched AIR on mobile;
it runs on Android 2.3+ devices only; and only devices that are matching the minimal requirements defined for the AIR runtime; that is to say, most of the smartphones and tablets, except cheap ones like ZTE products. When a device is not considered as powerful enough by adobe, the AIR based apps are not displayed in the stores.
Some recommendations:
The best way to organize your code is to create a project for each OS, with specifics assets (icons by example) and a specific manifest file (app.xml), and put all of your application code in a library used by these two projects. It will allow you to test your code (Flex mobile project can't be unit tested), and will avoid you permanent modifications of the manifest.
Worflow: it's usually faster to develop for Android, and then adapt you app for iOS, because it's faster to deploy and test on Android device (although you may use the Adobe Simulator most of the time).
Use the latest release of Apache Flex; it handles the high resolution devices. Forget Adobe's release (4.7 and lower)
Test quickly and often on mobile, especially for the responsive aspects.
Use FXG instead of bitmap graphics each time it's possible (i.e. if they arent animated); it's lighter and very easy to scale.
Mad Components
Alternatively, you may consider using Mad Components instead of Flex.
Flex was not designed for mobile at first; MC was. So it's faster (looks like native), and much lighter (although you still need the embedded AIR runtime which weights 9 Mb).

Confusion regarding PhoneGap/Cordova

I have a webapp developed (game), based on HTML5 + CreateJS, but since Android lacks of standards, I've run into unsolvable issues for my webapp. That's why im recurring to PhoneGap.
Yet my confusion lies in the fact that I need to make this game into a phonegap app that runs on Android/iOS, using for each platform native specific stuff.
So, should I build 2 apps (one for each platform), all over again, or use the one I have and try to deploy it into different devices using phonegap?
The truth is I don't know how to approach this problem... can anyone help?
Best Regards.
Yes, you can use Cordova (PhoneGap) to create a cross platform mobile app. Basically, Cordova (PhoneGap is Adobe's version of Cordova) is an open source project that provides JavaScript API's for accessing native device functionality (like the Accelerometer or Camera.) Cordova also lets you package your app in the native application shell, so you put your app on the app store. Please see my other answer here about Cordova and hybrid apps: Beginning with Apache Cordova
If the game runs completely in HTML5, I think it would be easiest to just use that one codebase and integrate it with Cordova and then deploy to the various platforms - why rewrite the app twice if you don't need to?
However, if you are using native device functionality, you may need to develop your own Cordova/Phonegap plugins for use. This way, you can call regular Android/iOS code (Java or Objective-C code) that you write from your web app code with JavaScript. This might be more work, especially if you have never written in these languages.
Personally, since you already have a working HTML5 app, I'd just try to get it working with Cordova and see how it performs. If you really need some native specific stuff, then I'd try creating that "stuff" as a plugin. Rebuilding the app twice, once for Android and once for iOS seems like a pretty big waste of time to me.
The answer here is either yes or no.
Yes if you want to use some specific feature of the native code. For instance, iOS's default objects is beautiful itself, you can easily drag and drop it to build your application. However, it takes lots of time to rebuild for another platform. Specially, if you intend to create app/game for multiple platforms, it would be a nightmare.
HTML5 is much faster for you to approach several platforms. However, you can't get the best result on all platforms and all devices. I mean, it is really difficult to bring the max performance of the app on all devices. For this solution, I suggest HTML5 with some libraries such as LimeJS, Crafty, Impact, etc. or some tools such as Construct 2, etc. I used to use HTML5 with all those libraries but found out that Construct 2 is much better.
Instead of using phonegap, I recommend cocoonjs. Specially if your targets are iOS and Android platforms.
Hope that help.
Yeah, even the simplest game such as bubble buster would be difficult to make cross platform with different version of android webview and you need cross platform? I would suggest looking into something like Unity3D.

Embedding The Dart VM In A Desktop Graphical Stand - Alone Application

So I am writing a cross-platform (so far plans for Windows and Ubuntu) application for both the web and desktop.
This application
is expected to at times be moderately graphically intensive and perform a substantial amount of file IO. I am writing it in Dart. Which may seem like a
"funny" choice given the circumstances, however I did not want
to deal with any heavy API's or have two code bases (NaCl and GCC with two different libs).
In short I am using Dart to interact with an HTML web page, and noticed the Dart VM does
not interact with a webpage unless you are in Dartium. But I want a "desktop application" as well as a web application which eliminates Dartium as a choice, so alternately I plan to use a Qt Webview to make it look like a desktop app, but what I am wondering is would it be worth it to go through the trouble of embedding the Dart VM into my app? In doing so would it easily enough to get the Dart VM (running a dart script) to interact with the page in the Qt Webview (I am a bit new to Dart)? Thanks for reading!
Dartium will eventually be merged with Chromium, allowing your DART applications to run inside chrome directly as a web technology.
Once that merges, you can take advantage of the new Chrome Apps which allow you to have a desktop version of your web technologies. As such, you won't need to use Qt Webview, or embed dartVM into your native application; just use Chrome Apps.
~Main

Flash Builder: Mobile AS3 Project or Mobile Flex Project?

This month I started to play with Flash Builder because I don't have a mac to create native iPhone apps.
I have made a Flex Mobile Project and an AS3 Mobile project. Both do mostly exact the same and I see great differences in operation speed (AS3 version is much faster). Also the size of the AS3 version is less than the size of the Flex version when I deploy the project.
But one thing disappoints me, the size of a deployed AS3 app (Android) is still about 8MB. I think that is quite huge for a simple app, or is it normal? I did not test the iOS version because I am not an Apple Developer member (is there a trick to deploy an iOS app with fake certificates)?
Resources I have used in the apps:
Two images approx. 35kb in size
A StageWebView
I want to know:
What is the average size of a simple app when it is a native app (apk file)?
What is the difference between an AS3 app and a Flex app except the libraries that re used?
Is the AS3 app converted to C or another language?
Why is the apk so huge (IMO)?
Is there a trick to deploy an iOS app with fake certificates? (just for testing)
Thanks for the answer(s).
What is the average size of a simple app when it is native app (apk file)?
I have no idea. When you were comparing sizes; did you export a release build or a debug version? The full version of my app; using Captive Runtime is 12MB. That includes all the embedded images. I thought that roughly 8MB is the size of the embedded runtime. Of course, if you don't use Captive Runtime then the app will be smaller; but it will have a depency on the user having the runtime installed.
What is the difference between an AS3 app and a Flex app except the libraries that are used?
For all intents and purposes nothing. The Flex Framework will need to execute code to setup the framework and such. In theory this 'impact' is offset by the value that the framework brings.
- Is the AS3 app converted to C or other language?
Not for Android or Playbook. It relies on the Mobile AIR Runtime--which I assume is written as a native app somehow. For iOS there is a more in depth conversion taking place; but no on knows the exact magic sauce; but it the process is much more intensive than Android or Playbook and people believe that your code and the AIR Runtime is converted to Objective C somehow in a way that is not in violation of the Apple licensing agreement.
Why is the apk so huge (IMO)?
Huge is open to interpretation. Without seeing your full app code; it's tough to judge.
Is there a trick to deploy an iOS app with fake certificates? (just for testing)
I don't think so; although there may be possibilities on unlocked devices.
You would like to use Mobile AS3 Project if you want you apps to be smaller and your GUI mainly contains vector graphics and Mobile Flex Project if you prefer to use standart GUI Controls that comes together with Flex framework but adds overhead in size because of controls that come with it.
As of the other questions:
the size of the apps is different on mobile platforms. Typical iOS app is about 2MB - 20MB. It really depends on resources you store with your app. What might be important to you is not to overcome 20MB if not needed because 20MB+ apps require Wi-Fi connection to be downloaded.
(However you should export release build version only as mentioned by www.Flextras.com)
there is no fundamental difference between AS3 and Flex apps - they both compile to the same instructions that executes on targeted mobile platform.
as far as I know (being iOS developer myself) there is no workaround to deploy an iOS apps. You need to use Mac and become Apple Developer to deploy with valid certificate.
to make your app smaller try to pai special attention to the resources you add to the project. Although I believe the size is so big because of framework itself, you would like to use more vector graphics vs. bitmaps when compiling apps with Flash/Flex.
When you export for Android you have an option of embedding the air framework in the application, that way your users don't have to download air. you can export your application without air embed which will result in a much lighter application, however your users will need to download air runtime. http://cookbooks.adobe.com/post_How_do_I_create_an_AIR_application_for_Android_tha-19299.html

How to use persistenceJS in phonegap application?

We are building a field data collection tool that will be available in two versions:
Fully html5 -- directly
downloadable through your browser
(does not support camera access,
etc..).
Hybrid using phonegap --
installation required (does support
camera access, etc..).
In the html5 version we are using
persistenceJS to store data. Somehow this does not seem to work in the hybrid version and it would be nice to keep the code base as generic as possible.
Does anyone know about using persistenceJS in combination with phonegap?
Note 2011/04/04: In a prototype we have gotten persistenceJS to work in phoneGap. Probably some kind of library is interfering in some way.
Phonegap is kind to persistencejs.
The only potential trouble is with iOS, which made its websql storage non-persitent starting in iOS 5. In other words your database can be periodically removed by the operating system.
If you upgrade to Phonegap 1.6 and up, there is a built-in fix for this problem and your persistencejs will work just fine.