Professional Android 4 Application Development

Android SDK Features x 7
The Android SDK includes APIs for location-based hardware (such as GPS), the camera, audio, network
connections, Wi-Fi, Bluetooth, sensors (including accelerometers), NFC, the touchscreen, and
power management. You can explore the possibilities of some of Android’s hardware APIs in more
detail in Chapters 12 and 15–17.
Data Transfers Using Wi-Fi, Bluetooth, and NFC
Android offers rich support for transferring data between devices, including Bluetooth, Wi-Fi
Direct, and Android Beam. These technologies offer a rich variety of techniques for sharing data
between paired devices, depending on the hardware available on the underlying device, allowing
you to create innovative collaborative applications.
In addition, Android offers APIs to manage your network connections, Bluetooth connections, and
NFC tag reading.
Details on using Android’s communications APIs are available in Chapter 16,
“Bluetooth, NFC, Networks, and Wi-Fi.”
Maps, Geocoding, and Location-Based Services
Embedded map support enables you to create a range of map-based applications that leverage the
mobility of Android devices. Android lets you design user interfaces that include interactive Google
Maps that you can control programmatically and annotate using Android’s rich graphics library.
Android’s location-based services manage technologies such as GPS and Google’s network-based
location technology to determine the device’s current position. These services enforce an abstraction
from specific location-detecting technology and let you specify minimum requirements (e.g.,
accuracy or cost) rather than selecting a particular technology. This also means your location-based
applications will work no matter what technology the host device supports.
To combine maps with locations, Android includes an API for forward and reverse geocoding that
lets you find map coordinates for an address, and the address of a map position.
You’ll learn the details of using maps, the geocoder, and location-based services
in Chapter 13, “Maps, Geocoding, and Location-Based Services.”
Background Services
Android supports applications and services designed to run in the background while your application
isn’t being actively used.
Modern mobiles and tablets are by nature multifunction devices; however, their screen sizes and
interaction models mean that generally only one interactive application is visible at any time.
Platforms that don’t support background execution limit the viability of applications that don’t need
your constant attention.