Develop Reference

How to rapidly prototype an image recognition application using Machine learning & neural network?

Known that I'm very new in Machine learning.
I was thinking about a real world example of using Machine Learning
and Neural network in an application and I want to try it with a
mobile application who can handle image recognition with the front
camera after make an image of something(A cat for exemple).
I really need advice of tools to use to rapidly make a prototype of this application with a python backend that I will call via rest.
Thanks in advance.

I suggest if you are new to the machine learning algorithms, that you use an API from Google or Microsoft and get in touch with the flow and how it works .. Once you understand what are the inputs and outputs, you can try to replace the API for you own neural net, try to train it properly and collect results ..
Machine learning is not an easy concept and if you start big, there is a good chance that you'll get discouraged before you finish building it ... The API will provide you with a functional prototype very quickly and thus help you stay motivated to pursue it more ..
But to answer your question more directly, TensorFlow by Google is probably the most sophisticated tool for machine learning in general right now..
There is an excellent course for deep learning with TensorFlow made by Google on Udacity ..

You can follow PyImageSearch. It has lot of stuff related image processiong like face recognition and license Plate Recognition system. It also use neural networks.

Use an image recognition API, like google vision.
It is easy and fast to put in an application, and a lot more effective if you do not have experience and ressources in ML

I have done something similar for our company website. It is based on caffe though.
You can go through the source code here
However, it is a segmentation demo. You need to modify it a little.

Android Source Code- writing custom services to startup at boot

I'm currently trying to learn how to write custom services and have them start up at boot, all in the Android Source code.
Could anyone point me to the right references (books, online articles, etc) that discuss this specific topic and as well as understanding AOSP/Android operating system in general?

To learn how to write a custom Service you can look at the docs here.
You'll want to learn about Activities and their Lifecycle in the docs here
And you'll want to learn about the Application fundamentals in the docs here
Once you have an idea of how everything works fundamentally, there are tons of tutorials on the internet that will show you how to code specific things. A simple Google search will find you all of that.
Hope this helps!

How to integrate Flingo-API in Android

I want integrate Flingo-API in Android.
here is the link
Did any one know about this Filngo API integraion.

Take a look at this https://play.google.com/store/apps/details?id=info.send2tv
It uses the flingo API.
There are a lot of things that it could do... If you are interested go to flingo.org and post to the forum.

Easy game examples for Android

I want to develop games for Android.
What are the best ways to do 2D games?
Are there some good resources on developing simple games for someone new to Android?

NOTICE : I suggest to check out other answers with good examples. I have requested to unaccept this answer and accept https://stackoverflow.com/a/8322784/753603 answer
Well it all depends where you stand in matter of Android platform and knowledge of how it works?
Beginner
Than I would suggest start writing simple apps to add some GUI background images, and get familiar with lots of different data structures and how to deal with them. Read about background task execution such as AsyncTask.
Intermediate
Explore different Graphics engines for Android, I would suggest
http://www.andengine.org/
ANdEngine is game engine for android platform, It has lots of built in functionality which you can use for making games. Find tutorials on google there are lot lot lot and lot...and while I am writing this, some generous people are writing one for us :)
Expert in making game on other platform
Than also I would suggest google tutorials like this one,
http://www.codeproject.com/KB/android/androidBallGame.aspx
Again there are heaps of them. :)
Cheers enjoy!

You can start by reading the Android documentation about Graphics. After that, you can try numerous tutorials and sample codes in the Resources section. There are sub-sections available for you to learn from the sample codes:
JetBoy
http://developer.android.com/resources/samples/JetBoy/index.html
Lunar Lander http://developer.android.com/resources/samples/LunarLander/index.html
TicTacToe http://developer.android.com/resources/samples/TicTacToeMain/index.html
and so on.
Working link for donut-release2 / samples

Pretty Good documentation on How do I get started making Android games ,

Where to get detail description on understanding android

I found lots of books on android which give basic concept on android Example (calling Activity, Intent, service, broadcast receivers etc). But I want to know brief description on all these concept. in os level or in api level how does it work. Also how connection with wifi or 3g works in api level.
I want to know brief understanding on android. Can anyone suggest any tutorial or book to get detail understanding on android.
Thanks

Start with the Android Developer's Guide. http://developer.android.com/guide/index.html

I would recommend to buy a book. For me Professional Android 2 Application Development was really good. But probably now there is better (up to date) alternative.
Anyway I find reading books much easier starter than separate tutorials and articles.

If you want a really detailed view, just look at the source code.