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There are so many app stores for any kind of platform out there, but when I try to find a good store to buy and sell j2me apps, I find some, but no really big one or defacto standard like I was used to have for the palm os (sites like palmgear sell nearly every program ever made for the palm and not only a subset).
Is there a store which I havn't found yet? Or is the j2me market dead?
GetJar is pretty much the only cross-platforms J2ME appstore I would be comfortable in relying on as a developer.
Then, I would directly go to Mobile Network Operators and Handset Manufacturers appstores.
There is no standard app store for j2me apps, and nither didexist for any other platform until Apple had invented the iPhone one. Since the Apple app sotre, almost all vendors created one, such as OVI for Nokia, AppWorld for BlackBrry and the Windows Mobile Marketplace. Also Sun came up with the Java Store, but it aimed only at desktop apps at the moment.
Since there was a clear void, many companies have created stores for mobile apps, most of theme support non-j2me apps (Windows Mobile, Symbian, etc.). The two largest ones are Handango and GetJar. Of the new stores, OVI and AppWorld sell j2me apps. Other stores such as PocketGear and MobiHand sell BlackBerry apps as well, but not pure j2me ones.
Given that, it seems that most the applications in the j2me are sold via the operators' portals or stores (like AT&T Media Mall) or pre-installed on the devices themselves. The outcome of this is that it relatively hard to sell j2me app, comparing to the smartphone arena (iPhone, Android, Blackberry, etc.)
Nokia's Ovi store? Seems like the only one that's really actively promoted and fairly large.
http://www.ovi.com/services/
How about Handango?
Please look at Handango web page for Java ME IM+ for Skype app as sample.
Here is one link that seems to have good collection of Mobile Apps for J2ME devices not mentioned in any of the previous posts.
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I need to create a video player like pot player or vlc , that can play my personal codec ( like mp4 , mkv , ... ) for security reason
a player has a login page and the user has to sign in to play video in it
with out sign in the player doesn't work at all
for example
I have video name.mp4 and
I want this video convert to something like this :
name.xyz
this format (xyz) should only play in my player and only play in a person's computer who buy these videos
I need some info on how to create this player and this player Should not crack.
which language is perfect for this purpose?
I want a cross-platform app. ( support in Linux, Mac, Windows )
Please help me. I need this app very bad
just Need a small clue
It seems your goal is to achieve a situation where playback can only happen in players that you produce and trust. That way you can enforce only users who have paid will be able to access the video.
For that, you do not need custom codecs (also note that .mp4 or .mkv is not a codec, but is a container). What you need is DRM. What DRM does is encrypt the video, so that it can't be played without having the decryption keys. The player you then need would have to have some way to get those keys, and keep them secret on the device.
There are several commercial systems out there, that can be implemented at relatively low cost. For instance, Microsoft Azure has a solution for this: https://azure.microsoft.com/en-us/services/media-services/content-protection/
If you need offline playback though, things are a bit more complex. Another option could be https://castlabs.com/drmtoday/
If you want to support all the listed platforms, you will likely need to interact with 3 different major DRM systems. Microsoft PlayReady, Google Widevine and Apple FairPlay. Azure and DRMToday packages all those together, but you can also choose to implement them all yourself.
You most likely do not want to build your own DRM system. Not only, is it far to easy to make mistakes that render it unsecure in some manner, it's also a lot of engineering effort, and way more costly to do than just using the existing systems.
Ok, so practically it's impossible to achieve what you want, because anyone who have access to these videos can record them and share for free. Also, you can't just rename something from name.mp4 to name.xyz because the content it's still the same, even if the extension is changed.
However, if you have your own codec than it's ok for you, because the usual video players won't decrypt it because it's new. The part with the login page it's again a problem, you have to think if you create accounts. You create them based on what? Password? Then I can share my account with my buddy and we both watch and just one of us paid. Based on IP? Ok, but there are many dynamic IPs over there.
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I am interested in Bluetooth 4.0. Where to start adventure with it? If you have any materials, links, books I'll be very grateful. If you could share this knowledge. I would to use BT 4.0 to connect a PC (no matter what system) with a smart phone (eg. Windows Phone).
Right, I tried to quickly put together some relevant information that might help you. There is a big chance I have missed thing because this is a broad topic.
I am pretty sure you will find help here when you will have more specific questions.
Basically when it comes to Bluetooth (Smart, 4.0) devices and programming / connecting to them we can talk about two things:
Bluetooh Clients and Servers
Servers:
usually provide some data to clients. Think about a Heart rate monitor that captures someones heartrate and "stream" it so anyone who connects to the server will be able to read the data.
Clients:
On the other hand clients connect to servers (how obvious) to collect their data, or in some cases to write to them.
Bluetooth Profiles
Bluetooth devices (servers) have so called GATT (generic attribute) Profiles. These profiles describe a kind of unique set of Services. Each Service has different Characteristics. These characteristics hold the actual values.
Think about a Heart rate monitor (HRM). Thats a server. It measures heart rate so clients that connect to it can read / collect it's data. Heart rate monitors have a specific Heart rate monitor GATT profile which describes services and inside the services there are the heart rate specific characteristics like: heart rate measurement, body sensor location, etc.
When a client wants to read these values it has to connect to the HRM, discover it's services and characteristics, then read the values from the discovered characteristics.
Async
It might be obvious but Bluetooth programming (implementing server / client connection and data transfer) is async. It means the client sends something then waits till the server answers then can the it progress to the next step.
Your whole software has to be implemented keeping async programming design in mind.
Documentation
I have to say I found the iOS documentation and support very useful when I developed my first bluetooth app.Android was somewhat more difficult for me because of the lack of examples I found. Also general bluetooth 4.0 support only became available since Android 4.3. (different bluetooth chip manufacturers in different Android phones had different low level bluetooth stack so to use them one had to write native bluetooth code for each different chip with their own SDK - prior to Android 4.3)
Bluetooth.org
I would suggest to start with this:
https://developer.bluetooth.org/DevelopmentResources/Pages/Quick-Start-Kit.aspx
https://developer.bluetooth.org/TechnologyOverview/Pages/Technology-Overview.aspx
https://developer.bluetooth.org/DevelopmentResources/Pages/default.aspx
https://developer.bluetooth.org/gatt/Pages/default.aspx
iOS
It won't hurt if you read about Core-bluetooth framework, which is the iOS approach even if you don't plan to develop on iOS. Since it is well documented it might give you a better overall understanding:
https://developer.apple.com/library/ios/documentation/NetworkingInternetWeb/Conceptual/CoreBluetooth_concepts/AboutCoreBluetooth/Introduction.html
Android
Same for android:
http://developer.android.com/guide/topics/connectivity/bluetooth-le.html
Windows 8
http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj207007%28v=vs.105%29.aspx
I've found "Bluetooth Low Energy: The Developer's Handbook" by Robin Heydon very useful. It deals with all the little details so you can understand how things are working on the lower level.
As a reference, I've found the Bluetooth specification PDF very useful (though it's sometimes hard to find what you need). It looks like they just released a 4.1 version here: https://www.bluetooth.org/en-us/specification/adopted-specifications
EDIT: both references aren't specific to any particular implementation, so I'm not sure how much they'd help if you wanted to learn something specific like iOS BLE or Android BLE.
I need to develop mobile application, so I decided to develop the application on J2ME.
This application must be support for Blackberry mobile, in this application we are using google maps, so can I use the J2ME software and if I develop the application in j2me how many types of mobile can support my application?
If any better software is there for supporting different mobile please suggest me.
I already developed the application in Android, this software supports few mobile, so I need to develop the application which mobiles are not supporting the android.
J2ME used to be the most widely deployed runtime on mobile phones wordwide (it may still be, depending on when you read this and the amount of Android phones sold by then).
These days, there are many phones that don't support it:
- closed phones (they don't let you install any application)
- Android
- iPhone
- BlackBerry 10
- The Palm WebOS phones
- I don't know whether the Samsung Bada phones support J2ME
- I expect that most of the mobile linux handsets (Maemo, Meego, Limo, Sailfish...) don't include J2ME by default. They tend to prefer a port of the Android runtime
- ...
The problem in developing an application that needs to support many handset models in many different countries is J2ME's curse: the dreaded fragmentation.
J2ME itself usually means the JSR-118 specification, along with a whole bunch of other optional APIs specified in JSR-75, JSR-82, JSR-120, JSR-135, JSR-139, JSR-172, JSR-177, JSR-179, JSR-180, JSR-184, JSR-185, JSR-205, JSR-211, JSR-226, JSR-229, JSR-234, JSR-238, JSR-239, JSR-248, JSR-256. You can see them all here.
These specifications have been interpreted differently by different companies implementing J2ME and they are often too generic to ensure the same piece of code to work identically on different phones.
Different mobile network operators also impose different requirements that sometime force mobile phone manufacturers to change the way their implementation of J2ME works based on who subsidizes the handset.
Operators can also modify data that goes through their mobile network.
I've been tasked with using WURFUL to determine whether or not a mobile browser is capable of downloading a J2ME app developed by my company.
I first thought I could use the "device_os" tag and filter by that, however, I'm unsure what the complete list of J2ME OS's are... any ideas?
I've been told there are no MIDP requirements, and that the application will run on any J2ME-supported handset (with two specific resolutions, which I already know how to query)
Thanks in advance.
There is no way to know all the OSes that support J2ME. Mainly because most feature handset comes with a proprietary OS which probably you have never seen before. It is a better idea try to identify the handset model and decide if it supports J2ME or not.
Another thing is, you may want to know which JSRs are supported by a specific handset. I do not know your application but probably you are using some optional JSRs that are not supported by some handsets although they have basic J2ME support.
Java ME SDK 3.0 includes a database of supported devices. Also there are other web sites that provides these kind of information. One example to those would be this J2ME Handsets web site.
If you are fine with just covering a large range of phones, you should include Symbian S60, S40, Windows Mobile, Blackberry and Android.
Symbian
Win Mob
Android
Almost every Sonyericsson phones
IMHO you don't have to worry about how many handsets support j2me because majority of the phones support it.
At least Symbian and Android.
Recently I started developing a J2ME app prototype. I noticed how difficult it is to develop a good looking UI. Consider developing an app in J2ME for booking flights interacting with webservice.
A website to book flights will be easy to develop with nice ui and can be accessed by browser on a handset. I understand not all handsets have browser but all the new and upcoming ones have browser and have big screen as well.
Is it a good idea to develop such a application in j2me which need to talk to webservice for it to work? Or j2me is only suitable for standalone apps?
Advantages of J2ME:
Can access phone resources, like file system, phone book and GPS. The last is very important in map applications.
You can build richer User Interfaces. It may be difficult as you say, but there are many GUI libraries that could assist you. On the contrary the UI for a mobile browser (you can't rely on CSS and javascript working) would be very poor.
Greater flexibility on the communication logic. You can encrypt/decrypt data, compress them, use SOAP web services. With the browser, your best bet would be to develop REST services.
Disadvantages of J2ME:
Midlets need to be signed. This has some cost and there are situations that even a signed app won't run properly in specific phones.
Developing a midlet to run in all types of phones is a nightmare. On the contrary, a well designed mobile web application would be displayed properly in all recent phones.
You need to have a channel for distributing your application. People would need to download it and get charged for the required bandwidth. You would need to care for angry customers having problems with the application. Things are easier with a web site.
J2ME apps are inevitably compared with native applications (iPhone, Windows Mobile, Symbian). Compared to these, they are very poor and many would find that paying for them or even using them isn't justified.
My conclusion: Nowadays real smart phones are becoming more popular and win an ever growing market share. Under these circumstances, the advantages of J2ME can't really overcome its restrictions. The only exception I could think of, is if to have to develop a GPS application. For all other cases, a mobile web site is a better idea.
There are a lot of misunderstanding and plain wrong statements in the previous answers.
I advice you to just do your research yourself. Nowadays you CAN develop really good looking apps with J2ME without writing your own GUI framework. Take a look at LWUIT really. For example they have a virtual keyboard as one of their touch screen functionalities and this you have on devices like the N97 which itself does not have a Virtual keyboard. BTW using LWUIT you have a Blackberry and Android port included if anyone cares.
Also Apps nowadays become the center stage on many platforms not just the iPhone. Look at the recent developments in this area like OVI, RIM, Samsung, SE, Orange World they all start with app shops.
"Getting people to use a website on their mobile phone is easier than getting them to download an application." this is just a claim without proof. you cannot say that like this. It depends on a lot of other factors. - Why should users type in your mobile url into the rather small screen again?
Anyway, this answer is probably too late so I'm not gonna write much more. The mobile industry is changing fast right now but there is not yet a alternative to J2ME for crossplatform development. Maybe in the future with better browsers and widget technolgies.
Just a short note, applications like google maps or gmail mobile probably don't use WebServices to talk to their server part. A WebService has a lot of overhead, especially when considering that mobile users are usually rated by the amount of data they transmit. The best way to perform communication between your client app and its server part is to use binary data over a socket connection.
I personally think it's really hard to make a consistent and reliable J2ME application that will run across a large set of mobile phones. Based on my experience, I would only develop a J2ME application (instead of a Web application) if it's a strict requirement - for example, to be able to view your bookings without being connected to the network. There are other costs associated with J2ME applications - the applications must be downloaded, the user will be asked if the application is allowed to connect to the network when it attempts to (there are exceptions for this case but I believe the application has to be signed by 3rd party company - more $$$ involved), you will have to maintain different versions of the application running on a variety of mobile phones (more complexity to the application), and so on...
Think about it this way - if you were developing a similar thing for a computer, would you build a desktop application or a web application? With the cellphones of today (many of which can access full-html sites with javascript - which means ajax), the proposition of the question is valid.
I thing a good rule of thumb should be: If what you're trying to achieve can be done with a mobile website - go for the website.
IMHO, apps should only be used to if they cant take advantage of the mobile hardware - like location, sound, video, 3d, pictures etc...
Even if the dev costs for the app were insignificant (they usually aren't), you'd have to offer some really amazing capabilities to make the users go through the trouble of downloading it.
(All of this is essentially true for J2ME/BREW. The iPhone is a little different as apps take the center stage)
One thing worth highlighting: the only standard way of deploying a MIDlet is via OTA download so you wouldn't expect a J2ME-capable phone to not have a web browser.
Mobile web browser like Webkit and Opera are getting better faster than J2ME (at least until MIDP3.0 starts shipping, if ever).
No matter which platform you choose, you will need to test your service on many devices. I don't think switching from J2ME to webapp makes a huge difference in that regard, because phone manufacturers keep changing the binaries that go into the phones firmwares.
Getting people to use a website on their mobile phone is easier than getting them to download an application. unless that application is already installed when they buy the phone, that is.
You might want to look at LWUIT for better and easier J2ME GUI.
One thing that J2ME will accomplish for a flight booking service is save battery life by not requiring constant network data transfer, thanks to the local storage mechanisms.
there are many great j2me apps that (need to) talk to webservices. just think of the google apps, like gmail mobile and maps for mobile. they are faster and easier to use than using the services via cell phone browser. so if you can design a good app, it's definitely worth it.
EDIT: also, a j2me app makes possible features that can't be provided by a web application: integration with phone features (address book, calendar), "call this number", location api, etc.
I think for business apps, or more text/data oriented things, a mobile web/wap site might be easier to maintain, since you won't have to deal with pushing client updates out to handsets.
For UI-intensive apps (maps, games, etc.), client apps are probably the way to go, so you can handle the more of the processing and rendering on the client side.
Both options are difficult though, since there are so many compatibility issues with phones. You might be best served by narrowing down what types of phones you want to support for your app. If you think most of your customers will be iPhone or Android phones, you can target those platforms (with either client apps or web apps) and avoid old-school j2me completely.
I hate WebApps on phones. They are slow and they don't work in a semi-connected environment.
J2ME apps can do local backups, bluetooth backups, bluetooth data sharing between 2 phones and better responsive UI. However that requires money,skill,time etc.
My main gripes with MIDP though is pushing software updates and wav real time mixing. Technically those are possible within the scope of MIDP but the goons at wheel are not very creative.