The document discusses location-based services (LBS) and best practices for programming using location APIs. It introduces LBS and outlines some of the technical challenges, including maintaining battery performance, varying accuracy levels, and continuous changes in location technologies. The document then provides recommendations for deciding on location requirements upfront and using criteria to select the best location provider. It suggests practices like implementing a back off pattern to reduce accuracy needs over time and monitoring battery usage.

1. Location API and programming
practices
Introduction to
programming using Location API
Amrit Sanjeev
Bangalore Android User Group

2. What’s on the agenda today ?
Introduction Challenges Best
to LBS practices
Let go and find where our users are 

3. Introduction to LBS
Things to keep in mind before you create your world changing LBS

4. What is a location based service ?
―A location-based service (LBS) is an
information or entertainment service, which is
accessible with mobile devices through the
mobile network and which uses information on
the geographical position of the mobile device.‖

5. Is it the hot tech of today ??
• Not really !!! But there is a lot of potential
• Gartner (2009) identifies the LBS will be the #2 mobile
application for 2012 because of its perceived high user
value and its influence on user loyalty.

6. Some interesting stats
• people where
63% aware of LBS
• report having
52% used LBS • 32% use it every month
• 10% use it every day
• thought it was
94% valuable
• 18% tell others their location
• Expose location without consent 84%
• Identity theft 84%
• expressed
52% concerns • Loss of privacy 84%

7. Why is LBS so important
Need for
services
on the
move .
Better Availability
data of
networks hardware
LBS
popularity
GPS
Better hardware
batteries in more
devices

8. LBS Growth Factors
Success of new
Growth of mobile
digital business
advertising.
models.
Increasing
Increased speeds and
smartphone broader
adoption. coverage of
Growth mobile networks.
of LBS

9. Challenges in deploying
LBS
Things that are slowing it down

10. LBS : Aspects to work on
Control
(Legal)
Security Trust
(Technolo
gical)
LBS (Social)
Privacy
(Ethical)

11. Obstacles in LBS adoption
Privacy concerns.
Security concerns
Two-thirds of advertising companies aren’t using LBS (2011 data).
General awareness is only around 30%.
Device user experience

12. Technical Challenges
• Maintaining battery performance
• Varying accuracy
• Multiple providers ( GPS , WIFI etc)
• Continuous change
• Responsiveness

13. Best Practices
Things that you might wanna try in your application

14. Decide on your app location requirements upfront
How often do you need updates?
What happens when GPS and WIFI are disabled ?
How accurate do u need to be ?
What is the impact on battery life ?
What happens when location jumps ?

15. Best practices
• Specify a minimum update frequency.
• Specify a minimum update distance.
int freq = 10 * 60 * 1000 ; // 10 minutes
int distance = 500 ; // 500 meters
locationManager.requestLocationUpdates(provider, freq, distance, 1)

16. Best practices
• Use criteria to select a location provider
• Specify the criteria
– Allowable power drain
– Required accuracy
– Need for additional parameters like altitude, bearing , speed etc
• Find the best location provider based on your criteria
• Relax requirement till you find a provider
• Can limit to only active providers
• Can use all matching providers

17. Best practices
Criteria criteria = new Criteria() ;
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
String provider = locationManager.getBestProvider(criteria, true);

18. Some best practices
• Reduce the latency for getting your first
location fix by retrieving the last known
location from the Location Manager each
time the app is resumed.
• If there is one or more locations available
from within the allowed latency, return the
most accurate one. If not, we simply return
the most recent result.

19. Best practices
• Implement a back off pattern
– Use multiple location providers
• Fine and course
• High and low frequency /distance
• Remove listeners as accuracy improves
• Monitor battery and reduce functionality to
save power .
– Change frequency of updates
– Disable location change receivers

20. Best practices
• Network location provider — tend to return results
faster than the more accurate options
• Requesting location updates (particularly using the
GPS) while your app isn’t in the foreground is poor
practice, as it can significantly impact battery life.
• Register Passive Location Changed Receiver that
allows you to receive background updates even
when the application has been killed by the
system to free resources.

21. Q&A