Entries Tagged as 'Android'

Summary of the Android 2.2 Announcements Made at Google I/O Yesterday

Android , Android development No Comments »

So yesterday, during the first half of the morning keynote at the Google I/O conference, Google made several announcements about the latest version of the Android OS:  version 2.2, codenamed "Froyo."  Here are several links to pages that go through the announcements:

http://android-developers.blogspot.com/2010/05/android-22-and-developers-goodies.html

http://www.dzone.com/links/r/android_22_and_beyond.html

http://www.blog.droidweb.com/2010/05/android-2-2-annoucned-at-google-io-what-it-means-for-you/

A couple of additional notes:

  • One of the announcements was that you could initiate actions on your phone via the "the cloud" (the Internet). In the demo, the presenter's assistant was able to get driving directions on his laptop using the Chrome browser and then send those directions to his Android phone by clicking on a certain link. The presenter said that browser initiated an "intent" on the Android device.

    In Android development, an Intent is a messaging object directed at a component (an Activity, a Service, or a Broadcast Receiver) within an Android application and delivers data to the component. Normally, an Intent can either be explicitly addressed to a specific component by name, or it can be implicitly targeted towards any component whose intent filters make them capable of receiving the intent. I'm curious to see how Google will implement this feature to make sure this capability isn't used maliciously.

  • Another announcement was that Android 2.2 would allow developers and users to install applications on the SD card in the Android phone rather than in the phone's internal memory, something that many Android users have wanted for a long time.  The Android Developer site already has a documentation page up regarding this feature, which I glanced over.

    When they write an application using the API for Android 2.2 (apps written to an earlier API will NOT be movable to the SD card using the features in Android 2.2), developers can specify one of the following install locations within their application's manifest file:

    • "preferExternal": the app will initially be installed to the SD card automatically unless the SD card is full. The user will have the option to move it to internal storage if they like.

    • "auto": Android will determine the best location for the initial installation for the app, but again the user has the option of moving it.

    • "internalOnly": the app can only be installed in the internal memory of the device.

    The drawback to running an application from the SD card is that all application processes currently active on the SD card are killed whenever the user connects their Android device to their computer and chooses to mount the SD card as an external USB drive. Applications that use certain features can break when this situation occurs, and therefore such applications may have the "internalOnly" install setting in place to prevent problems.

    The documentation also points out that applications installed to the SD card will still store any private user data and databases for the application in the internal memory. So the need for a way to back up the application data was still needed even with the SD installation option, hence the announced feature in 2.2 that application data could be backed up to the cloud.

Developing Native Android Applications: Not as Hard As You Might Think

Android , Android development 6 Comments »

Two months ago, my boss asked me to try and build a native Android application based on the mobile website I had created for the university's annual Maryland Day festival. Both he and I are part of an IT initiative in our department tasked with figuring out how best to provide IT services to smartphone users on campus, and while we have in-house expertise in iPhone development, none of us were familiar with what would be involved in building Android applications. So he asked me to give it a shot.

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HTML 5 Geolocation Functions and Mobile Web Browsers: Show the User Where They Are (Sort Of)

Android , JavaScript , Miscellaneous , Web development 8 Comments »

Every April, the University of Maryland holds a huge open-house event called Maryland Day that draws 60,000+ visitors to the campus to view exhibits highlighting the research conducted at the university and participate in various events and activities. All of the event details are entered into a ColdFusion application, and one of those details is the GPS coordinates (latitude and longitude) of where each event is taking place so visitors to the website can see where the events are located on Google Maps.

Now that smartphones are becoming more prevalent, I wanted to see if it was possible to build a web application that would show the user where they were currently located and then show them on a map how to get from their current location to a particular event.

So I did some research and learned that HTML 5 comes with a Geolocation API. This API allows you to execute Javascript functions within the navigator.geolocation object built into the browser that retrieve the supposed latitude and longitude coordinates of where the browser is located (and, if available, the altitude, heading, and speed at which the browser is moving).

Using the code examples I found on the Gelocation API page on the W3C website and on Oliver Wehren's geolocation demo page, I was able to create my own test page for determining my location and marking it on Google Maps. I then tried using the page with my Motorola Droid, my iPod Touch, and my manager's iPhone.

The default web browsers on all three devices implemented the Geolocation API (my preferred browser on my Droid, the Dolphin Browser, did not). Each of the browsers displayed a confirmation dialog asking for permission to share my location information with the web page (as mandated by the standard), and once I permitted the information to be used, my test page was able to place a marker denoting my location on the map.

However, the location wasn't as accurate as I had hoped. Although the API was coded to accept location data from the on-board GPS system in a mobile device, neither the iPhone nor the Droid seem to provide GPS data to the browser. If I was connected to the campus wireless network, my location was determined via the network topography, and it could be off by as much as 150 feet or so. The accuracy was even worse if I was relying solely on 3G: in that scenario, but the iPhone and the Droid had me located on the side of a state road on the outskirts of campus, a good twenty minute walk from where I actually was. I have no idea what caused both devices to pick that particular spot, as there certainly wasn't a cell tower anywhere near that location.

So I came to the conclusion that while the Geolocation API could be used to determine what town, city, or general area a user was currently in, it wasn't accurate enough (at least with these browsers in these devices) to provide walking or driving directions within a small area, especially given the fact that many of the users for the service I had in mind would only have access to the Internet via a 3G connection.

But if someone knows of a way of increasing the location accuracy of the Geolocation API, a way that doesn't require the end-user to modify their mobile browser in order to make it work, I'd love to hear about it.

Droid: My Experience So Far

Android , Miscellaneous 2 Comments »

So I went ahead and bought a Droid this past Friday. I haven't had a huge amount of time to play with it yet, but I thought I'd share some of my experiences so far:

  • I'm not sold on the physical keyboard yet. The keys are very close together, so if you have decent-sized thumbs like I do, you have to really focus on your typing to avoid hitting two keys at once. Having said that, I have gotten better at it since my first day.

  • I like the on-screen keyboards. The haptic feedback (the slight vibration when you hit a key) is nice, and I like the row of word suggestions that's displayed under the typing area as you type. I prefer it over the virtual keyboard of my iPod Touch.

  • The screen is beautiful. I haven't had a chance to play any videos on it, but the application icons on the screen make the iPod icons look "soft" in comparison.

  • The web browser is on par with the Safari browser on the iPod (no real surprise, as they both employ the webkit engine). The Android browser does not have multi-touch, so you can't pinch the web pages, but it lets you double-tap on the page to magnify it and I find that sufficent. Web pages load about as quickly as I expected (a bit slower over 3G, obviously).

  • The new Google Maps Navigation with turn-by-turn directions is as cool as reported. I used it twice just to see how it worked, and it gave me perfect directions and was quick to recalculate the route when I went a different direction.

  • I like having the ability to have widgets on my screen for things like the weather and Twitter, but because the default UI for Android only gives you three screens to work with, you have to be judicious about which widgets you want to display (though it's easy to add and remove widgets).

  • I really like the notification system. If the Droid is "on" (i.e. the screen is lit), the notification/status bar at the top of the screen will denote if you have any new Gmail messages or Twitter updates with icons, and you can drag down the notification window to see a summary of what's going on. If the Droid screen is off/dark, and there are updates, an LED light in the upper right corner will flash. It even flashes different colors for different applications:  green if there's a new Gmail message, blue if Twidroid (my main Twitter app) has received new tweets.

  • Android phones do not have a set media management programs like iTunes, so you have two options for copying your media files onto your phone: you can simply mount the phone's SD card as a hard drive via USB and copy the files manually, or you can download a program like doubleTwist (Windows only) or Salling Media Sync (Windows/Mac) that inspects your iTunes library and playlists and copies any non-DRM media over to the Droid. I couldn't get doubleTwist to synch my files (I suspect it just needs to be updated to handle the Droid), but Salling Media Sync was able to copy over the iTunes playlists I selected.

  • Some Droid users have reported problems with the auto-focus on the camera for still shots.  I personally haven't experienced that problem. I was surprised that there was no way to specify what it was you wanted the lens to focus on within the shot: double-tapping on the screen causes it to zoom in rather than select the subject. Despite that, the few pictures I've taken look pretty good to me. There are one or two camera apps in the Android Marketplace, so I imagine that better camera applications will be developed for the Droid eventually.

  • Speaking of the Android Marketplace, it's easily accessible via the Marketplace app on the Droid. You can find apps by category or via the search bar, and each application is listed with a price (quite a few are free or donation-ware) and a rating. It's easy to download an app, try it out, and then uninstall/delete it if it's not to your liking.

  • The battery seems sufficient to me, though I probably haven't used it as heavily as some folks would. Since every app you turn on (and some apps start up automatically) stays on unless you explicitly kill it, having a program that can selectively turn off running apps like Advanced Task Killer if you don't want to waste power.  I also downloaded a widget that lets me selectively turn off the different radios/receivers on the Droid (WiFi, Bluetooth, GPS) if I'm not using them.

  • The ability to multitask is sweet. I had the music player on while I drove to work this morning when it occurred to me that I hadn't shut off the WiFi radio on the Droid. So while I was stopped at a traffic light, I hit the Home button, swiped over to the right screen where my radio manager widget was, turned off the WiFi, and went back to the music player, all without missing a note of the song.

If anyone has any questions about the Droid, feel free to ask, and I'll answer them if I can.