It’s a remote-control helicopter with a twist. Instead of having a dedicated remote control, it has an infra-red emitter that plugs into your phone. And you control it using an application you can download from your phone’s marketplace. And it doesn’t just work on the iPhone, there are also a number of Android phones that it supports. It was nice to find out it supports the phone I have, the Samsung Galaxy S II, so all I had to do was download the app and give it a try.

The helicopter handles well. It has an in-built gyroscope which makes it quite easy to control. I haven’t played with it much so far, as I tried it out in the sitting room and kept worrying that I would crash it into the TV. I’ll try it outdoors one of these days. In fact, the application has a “Demo” button in it, but I wasn’t ready to just let it go berserk in the living room. The app even has a mode where can control the helicopter just by tilting the phone in the direction you want the helicopter to go. Here’s a short video where you can see the chopper in action:

Very much recommended, and you get get one for yourself down at Paramount Zone, where you can find it in their Christmas Gifts section. I think my kids are too young for it just yet. Which means I get to play it all by myself. Muhahaha!

However, this evening I was going to play with some Android development, so I started loading up bits I needed. First on was the Java JDK. I had a choice of 64-bit or 32-bit, so went for the 64-bit version. All was fine and dandy till I tried installing the Android SDK, at which point I was presented with an error telling me that the “Java SE Development Kit (JDK) not found”

Backtracking, I uninstalled the 64-bit JDK, installed the 32-bit version and lo and behind, the Android SDK is now on my machine.

However, when I proceeded to the actual tool I wanted to have a play with, called Appcelerator Titanium, I just hit a brick wall:

Try as I might, I just couldn’t get the darn thing running on my 64-bit platform. I guess I’ll just have to set up a 32-bit VM and get it running from there, but no more time for play today, so I’ll have to shelf it for another day

Well, the latest experimental drop of the ROM: CyanogenMod 6.1.0 RC 2 has an awesome feature which has got to be my favourite feature in a long time: Lockscreen Gestures. You know how it is, you need to take a photo in a hurry, so you dig into your pocket for your phone, scramble to unlock it, get the lock code wrong, unlock again, try to find the camera icon, miss it, open the Gallery instead, go back, hit the camera .. and your photo opportunity it gone! Well, Lockscreen Gestures lets you go straight from the lockscreen to your favourite app, without having to navigate or search for it. I’ve only just started playing with it, but it really works for when you need snappy access to an application. These are the gestures I have at the moment:

If you want to try Cyanogenmod on your phone, check out if there’s a version for you under the stable mods. If you need more information, check out the wiki, or drop me a Tweet

The images on my phone are now tiny and on the Tattoo are all jammed up together. This is caused by the fact that the images sizes are set to 100 pixels across. I’m going to have to rethink how the pictures are sized and use the display width to figure out the proper width for the images. In retrospect this is what I should have done in the first place, but hey, I believe in learning through doing and you can’t learn without making mistakes.

So, onto reading about density independence and the other joys of supporting multiple screen types.

It’s a pretty simple application that shows you some of the sights around the Isle of Man, together with a small description of what you”re viewing. I’ll be adding more functionality to it in the future, but in the meantime you can see it on the Market view on AppBrain: Isle of Man Views

Next feature I’ll be working on is to show a map of the photo you’re looking at.

Awesome stuff!

and

If you see me around, just ask for a demo, I’d be delighted to oblige

photo credit: Josh Russell

There are four building blocks to an Android application:

* Activity
* Intent Receiver
* Service
* Content Provider

Not every application needs to have all four, but your application will be written with some combination of these.

Once you have decided what components you need for your application, you should list them in a file called AndroidManifest.xml. This is an XML file where you declare the components of your application and what their capabilities and requirements are. See the Android manifest file documentation for complete details.

Activity
Activities are the most common of the four Android building blocks. An activity is usually a single screen in your application. Each activity is implemented as a single class that extends the Activity base class. Your class will display a user interface composed of Views and respond to events. Most applications consist of multiple screens. For example, a text messaging application might have one screen that shows a list of contacts to send messages to, a second screen to write the message to the chosen contact, and other screens to review old messages or change settings. Each of these screens would be implemented as an activity. Moving to another screen is accomplished by a starting a new activity. In some cases an activity may return a value to the previous activity — for example an activity that lets the user pick a photo would return the chosen photo to the caller.

When a new screen opens, the previous screen is paused and put onto a history stack. The user can navigate backward through previously opened screens in the history. Screens can also choose to be removed from the history stack when it would be inappropriate for them to remain. Android retains history stacks for each application launched from the home screen.

Intent and Intent Filters
Android uses a special class called an Intent to move from screen to screen. An intent describes what an application wants done. The two most important parts of the intent data structure are the action and the data to act upon. Typical values for action are MAIN (the front door of the activity), VIEW, PICK, EDIT, etc. The data is expressed as a URI. For example, to view contact information for a person, you would create an intent with the VIEW action and the data set to a URI representing that person.

There is a related class called an IntentFilter. While an intent is effectively a request to do something, an intent filter is a description of what intents an activity (or intent receiver, see below) is capable of handling. An activity that is able to display contact information for a person would publish an IntentFilter that said that it knows how to handle the action VIEW when applied to data representing a person. Activities publish their IntentFilters in the AndroidManifest.xml file.

Navigating from screen to screen is accomplished by resolving intents. To navigate forward, an activity calls startActivity(myIntent). The system then looks at the intent filters for all installed applications and picks the activity whose intent filters best matches myIntent. The new activity is informed of the intent, which causes it to be launched. The process of resolving intents happens at run time when startActivity is called, which offers two key benefits:

* Activities can reuse functionality from other components simply by making a request in the form of an Intent
* Activities can be replaced at any time by a new Activity with an equivalent IntentFilter

Intent Receiver
You can use an IntentReceiver when you want code in your application to execute in reaction to an external event, for example, when the phone rings, or when the data network is available, or when it’s midnight. Intent receivers do not display a UI, although they may use the NotificationManager to alert the user if something interesting has happened. Intent receivers are registered in AndroidManifest.xml, but you can also register them from code using Context.registerReceiver(). Your application does not have to be running for its intent receivers to be called; the system will start your application, if necessary, when an intent receiver is triggered. Applications can also send their own intent broadcasts to others with Context.broadcastIntent().

Service
A Service is code that is long-lived and runs without a UI. A good example of this is a media player playing songs from a play list. In a media player application, there would probably be one or more activities that allow the user to choose songs and start playing them. However, the music playback itself should not be handled by an activity because the user will expect the music to keep playing even after navigating to a new screen. In this case, the media player activity could start a service using Context.startService() to to run in the background to keep the music going. The system will then keep the music playback service running until it has finished. (You can learn more about the priority given to services in the system by reading Lifecycle of an Android Application.) Note that you can connect to a service (and start it if it’s not already running) with the Context.bindService() method. When connected to a service, you can communicate with it through an interface exposed by the service. For the music service, this might allow you to pause, rewind, etc.

Content Provider
Applications can store their data in files, an SQLite database, or any other mechanism that makes sense. A content provider, however, is useful if you want your application’s data to be shared with other applications. A content provider is a class that implements a standard set of methods to let other applications store and retrieve the type of data that is handled by that content provider.

To get more details on content providers, see Accessing Content Providers.

http://code.google.com/android/intro/anatomy.html

Portions of this page are reproduced from work created and shared by Google and used according to terms described in the Creative Commons 2.5 Attribution License. – Originally posted in Android Community Forums, but excellent enough to share.

Here’s my list of favourites in descending order:

• Google Skymap: Here’s a cute little app. It’s essential if you’re into astronomy, but if, like me you have just a passing curiosity, it’s still a lot of fun. It shows you a map pointing out the brightest naked-eye stars, planets, sun and moon, constellation lines, horizon, cardinal points, and Messier Objects. The awesome part though, is that it uses the phone’s GPS, accelerometer and compass to figure out where you are, where you are pointing your phone and therefore which part of the sky you’re looking at. It therefore shows you the night sky you’re looking at and helps you identify all the different objects you’re looking at.
  

  Read more about Google SkyMap

• Twidroid: An awesome Twitter client that does everything you may want from a Twitter client and then some. It can use your phone’s GPS or other location-based services to automatically post your location and the phone’s camera to snap and upload photos right to yourTwitter account. It does all the great things the best Twitter clients do, lets you retweet things efficiently, reply to tweets and DM people really easily. If you’re a Twitter fiend, it’s very much recommended.
  

  Read more about Twidroid.

• Shazam: Ever seen an application that looks just like magic? Well Shazam is one of those. Let’s say you’re sitting in the car and a great song comes on the radio. Don’t you hate it when the song finishes and you never learn what it was? Well, with Shazam, all you do if fire up the app, let it listen to a few seconds on your song and bang, it comes back with the name of the song, the artist and all the information you could ever want to learn about it.
  

  Read more about Shazam.

• Shopsavvy: Here’s another interesting application. It lets you scan a barcode on a book and tells you what the book is, giving you quick access to reviews about it. Big deal you might say; but there’s also another aspect to it. It looks for the book online and tells you what the prices are from a number of different online retailers; so if you’re in a bookstore, you can immediately tell if you have a good deal or not. But wait, there’s another twist. Using location-based services it also does a check of other book retailers in the area and check what they’re selling the book at. So, if the shop you’re checking the price in is too expensive, you can just nip next door and get it from the cheaper place.
  

  Read more about Shopsavvy

• Wikitude: This is just the most awesome application ever. Imagine you’re driving along and see a building on the horizon. You have no idea what it is. Well, Wikitude checks where you are, pings Wikipedia pulling down landmarks in the area, and uses the compass and camera in your phone to superimpose the inforamtion on the image you’re looking at. It’s a type of technology called Augmented Reality and you have to see it to realise just how awesome it it.
  

  Read more about Wikitude

These are just five of the applications I have tried so far. There are others out there that I haven’t got to yet, one particular area I’m interested in is live video streaming services, but I just haven’t managed to find anything that works for me yet. I also have a number of games that are going into a similar post to this, that is .. when I get round to posting it. There’s some amazing stuff in there, so if you have an Android phone and haven’t seen one of the five above, just pop onto the Market and give them a try. They’re all free!

I’ve been looking to upgrade my phone for some time now, and this video REALLY got my juices flowing. Android seems to be getting more and more compelling with every release and “Cupcake” makes it even more attractive. I’ll be taking the plunge .. soon .. very soon …