(4) What does Mobile mean?

• Laptops are mobile devices
  • in fact, any non-mainframe computer is a mobile device
  • laptops are a popular point in a design continuum
• Mobile is better defined by settings than by devices
• Mobile settings can be defined by various properties
  • usage of a device with constrained capabilities
  • more task-oriented than exploration
  • location in many cases is a relevant factor
  • circumstances allow less focus on interaction and presentation

(5) Mobile Computers

(6) Outdoor Offline Users

(7) Social Connections

(8) Location Search

(9) Mobile Guidance

(10) Mobile E-Books

(11) Producers vs. Consumers

• Mobile does not specify what the mobile part is
  • the service may provide access to information with a mobile component
  • the service may be consumed in mobile settings
  • in many cases, both of these issues are combined
• Mobile Producers require the service to provide location-based information
  • clients/users must be able to request information based on location
  • the protocol for accessing the service contains location concepts
  • it may be irrelevant for the service where the client is located
• Mobile Consumers are accessing services/data from mobile settings
  • clients/users may have a way to determine their location
  • data can be stored locally or accessed over a network
  • location of the client/user is an important parameter
• All these issues can become complicated and distributed across services
  1. use a camera to take pictures on a trip (tagged with timestamps)
  2. carry a GPS receiver to create a time-coded GPS track
  3. process the pictures to add location tags based on their timestamps

(12) Producing Mobile Data

View Larger Map [http://maps.google.com/maps?f=q&source=embed&hl=en&geocode=&q=http:%2F%2Fdret.net%2Flectures%2Fmobapp-spring10%2Fsrc%2Ffiretrail.gpx&sll=37.875733,-122.265092&sspn=0.015582,0.02311&ie=UTF8&t=p&ll=37.87526,-122.243843&spn=0.04065,0.042915&z=14]

(13) Consuming Mobile Data

(15) Professional Users

• Exclusively task-oriented
• Regulatory and legislative side-effects
  • any medical application must be very secure (patient privacy)
  • sometimes it may be necessary to be able to trace everything (audits)
• Device landscapes can be managed top-down
  • Blackberry's are not especially good, but very convenient for centralized IT
  • lock-in [http://en.wikipedia.org/wiki/Vendor_lock-in] often has short-time savings and long-term costs

(16) Social Users

• Goal-oriented instead of task-oriented
• Choice of technology or channel is opportunistic
• Technology must be simple to use and convenient
  • little need for latest technologies or devices
• Cost often is an important issue

(17) Exploring Users

• No specific goal or task orientation
• Technology use as entertainment
  • technology itself is used as entertainment
• Typically less cost-sensitive than social users

(19) Device Differences

• Screen size (15" to 1")
• Screen technology (color or monochrome, LCD or e-ink)
• Keyboard input (regular, virtual, numbers only, T9)
• Pointing device (none, mouse, trackball, touchscreen)
• Device functions (video, audio, phone, Wi-Fi)
• Internal environment (OS, runtime environment, APIs, content formats)

(20) Mobile Computers

(21) Smartphones

(22) Dedicated Devices

(23) Pervasive Computing

(25) Web-Based Applications

• Server-side applications serve Web pages
• Client-side browsers let the user navigate pages
• More diversity than in the pre-mobile age
  • Devices and platforms and browsers are more diverse
• Easiest way to make content available to users worldwide
  • limitations based on HTML/CSS/scripting and the local platform
  • HTML5 and more powerful devices are narrowing the gap

(26) Runtime Environments

• Virtual machines as hardware abstraction
• Decoupling between concrete OS and application runtime environment
• Building a complete and good virtual platforms is hard
  • performance can be problematic (optimization possible but hard)
  • security is a big problem (a complete new set of attack points)
• Interesting as a hybrid approach between Web and native

(27) Native Applications

• Built specifically for one platform (OS plus runtime environment)
• Allows the highest degree of sophistication
  • access to all capabilities of the platform
• Requires the highest degree of developer sophistication
  • programming often requires a complex non-scripting language
  • the programming environment is complex and hard to learn
• Economically only feasible for popular platforms

(29) Connecting Clients and Servers

• Worldwide there are two dominant information networks
  • the worldwide phone network
  • the Internet
• Connections change over time
  • for a long time there only was the postal service
  • telegraph services were the first global immediate services