How easy is to get location data?

Data can be purchased

• Danezis et al (2005)
• Median value placed on data by students of £10

• Cvrcek et al (2006)

• Variations by country, purpose and length of observation

Data can be exchanged for chance to win

• Krumm (2007)

• Data donated for 1/100 chance to win a $200 MP3 player

Data can be exchanged for services

• Location based apps etc.

Data could be obtained without permission

• iPhone tracking etc.