Introduction. Mobile GIS emerged in the mid-1990s to meet the needs of field work such as surveying and utility maintenance.

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1 Mobile GIS

2 Introduction With more than 6.8 billion mobile cellular subscribers, (2013), wireless communication and mobile computing have gained acceptance worldwide with speed that has surpassed many other technological innovations. Mobile GIS emerged in the mid-1990s to meet the needs of field work such as surveying and utility maintenance.

3 Introduction Early systems operated mainly in a disconnected mode. With radical advances in wireless communications, especially the operation of 3G networks, mobile GIS is increasingly connected to the Web, and thus becoming a part of Web GIS.

4 Uses and Benefits Mobile GIS can update the server with the latest information from the field. The Web server can, in turn, support mobile GIS with rich content and advanced analytics. Mobile GIS is needed by the general public as it is by organizations and professionals.

5 Uses and Benefits Consumer mapping applications provide location-based services (LBS) related to the location of the user. This leads to GIS on the go- to find things that are nearby, to get to places, and to locate friends. Mobile GIS can potentially be used by anyone, for anything, anytime, anywhere.

6 Uses and Benefits In the past decade, there has been no greater influence on GIS architecture than in the enormous improvements that have been made in computer networks. We are in the midst of a radical shift from wired to wireless communications, and from wired to wireless computer networks.

7 Concept Conceptually, there are 4 locations in a GIS: The location of the User (U) The location where the data is stored (D) The location where the data is being processed (P) The location of the subject of the GIS Project (S) Traditionally, U S, since the user is usually in the office, and the subject can be anywhere in the world.

8 Concept In Mobile GIS, U=S. That is, the user is usually located in the subject area; thus the user can see, touch, feel, hear and even smell the subject. For eg. First responders are right at the incident scene and they can record what they see, feel, hear and smell. Such information extends the awareness of those in command through observations from afar.

9 Mobile GIS- Functions and Applications The early applications of mobile GIS were often for in-vehicle navigation and field surveying. GIS data and software were preloaded and operated in a disconnect mode in the field. With advances in wireless communication, rich and powerful GIS services and applications are available over the web.

10 Mobile GIS- Functions and Applications Mobile GIS works well with following GIS functions: 1. Information capturing and updating: a. Mobile devices are portable b. Built-in GPS receivers allow for acquiring accurate location information c. Contemporary mobile devices with cameras and recorders allow for capturing rich geospatial information in several forms. 2. Dissemination: a. Mobile devices can bring GIS into the hands of billions, whether users are in the field, office, home or on the go. b. You can view maps and query what s around you on demand.

11 Mobile GIS- Functions and Applications Mobile GIS is relatively weak in the following GIS functions: 1. Storage: 2. Analysis: Mobile devices are not considered a robust platform for large databases. Because of limited computing power, it cannot provide the comprehensive and sophisticated analysis capabilities. 3. Presentation: Mobile screens cannot compare with desktop monitors in terms of size of presentation and depth of color

12 Mobile GIS- Functions and Applications There are two types of Mobile GIS Applications 1. Consumer Mobile GIS Applications: a. Where am I? b. What is around me? c. Where is the closest restaurant, bank, atm, gas station or store? d. How do I get from here to there? e. These applications usually fall under the umbrella of LBS- location based services. f. They all need to have basemaps and Point of interests. g. Main competition focuses on who has the most comprehensive and up-to-date basemaps and POIs, and who has the best usability and trendiest user interface. h. Eg. Google Maps, Bing for mobile, Mapquest etc.

13 Mobile GIS- Functions and Applications There are two types of Mobile GIS Applications 2. Enterprise Mobile GIS Applications: a. Developed for utility and infrastructure companies, public safety, law enforcement and government agencies. b. Field mapping, query and decision support c. Field inspection and inventory of assets d. Field Surveying e. Incident reporting f. Collaboration g. Tracking h. Functionality over Novelty

14 Advantages of Mobile GIS Mobile GIS has certain advantages over traditional desktop GIS. 1. Replacing paper-based workflows: Replace paper forms, redundant work process and improve currency and accuracy of data. 2. Mobility: Compact and portable. Mobile devices can extend GIS to areas where wiring is infeasible or costly, where its too hot or humid for normal computers to functions. 3. Large volumes of users: With more than 4 billion cell phone subscribers, mobile users have far exceeded the number of desktop computer users. Broadens the market for geospatial industry and provides tremendous potential for the use of geospatial science. 4. Location awareness: A number of technologies can be used to pinpoint the current location of a mobile device. 5. Versatile means of communication: Users of mobile GIS can communicate via voice, short message, photo, video, and the Web. 6. Near-real-time information: The application domain of mobile GIS is usually wherever an event is taking place and whenever a user needs information. Field events can be recorded and reported to the Web server in near-real time. Mobile GIS has the potential to monitor the spatial and temporal aspects of the world around us.

15 Mobile Devices Mobile devices can be classified in 4 categories: 1. Mobile Phones : IPhones, Samsungs etc. Allows for versatile communication 2. Pocket PCs: Handheld computers, more powerful mobile phones, hence provide a strong platform for mobile GIS 3. Portable PCs: Laptops, Tablet PCs etc. Relatively heavier, but more powerful. 4. Special Devices : Car GPS, Trimble Junos etc. For specialized tasks

16 Wireless Communications Wireless communications technologies vary in their speed, range and setup costs: 1. Bluetooth: Designed for short range communication about 10m. Applications include communication between mobile device and its peripherals such as GPS receiver and headset 2. WI-FI: Typical range of 100m, therefore limited in spatial coverage

17 Wireless Communications Wireless communications technologies vary in their speed, range and setup costs: 3. Cellular Networks: Cellular network covers wider areas. 1G: Analog Technique and transmits voice only. Mobile GIS cannot be built on this technology 2G and 2.5G: Digital network, supports voice and low speed data transmission(10 KBps). 2.5G is an updated version of 2G (384 KBps) Building mobile GIS in 2G and 2.5G faces a challenge of limited data transfer speeds. 3G: Currently available in many parts of the world. Data transmission speeds upto 2 MBps. Mobile GIS can be built on this technology 4G: Fourth Generation Technology, will provide data transmission speeds of about 100 MBps. The network will be built on LTE(Long Term Evolution), WiMax (Worldwide Interoperability of Microwave Access) or UMB (Ultra Mobile Bradband). Mobile GIS will thrive in the 4G era.

18 Mobile Positioning Technology The cornerstone of most mobile GIS applications is location awareness. The main mobile positioning technologies today are based on satellite cellular network Wi-Fi network IP address radio frequency identification (RFID)

19 Mobile Positioning Technology Navigation Satellite-Based Approach: GNSS- Global Navigation Satellite Systems allows small electronic receivers to determine their location by using the signals transmitted by satellites. The most commonly used satellite system is the U.S. Global Position System (GPS). Other systems include GLONASS, Beidou and Gallileo This approach is often used for applications where high accuracy is required such as in-vehicle navigation, field surveying and utility maintenance. The disadvantage is that satellite based accuracy can be reduced by satellite position, cloud cover and physical barriers such as high-rise buildings.

20 Mobile Positioning Technology Cellular Network-Based Approach The cellular network based positioning approach relies on the way the cellular site finds mobile devices in its service territory and routes calls or other types of communication services to them. Relatively lower accuracy Can be implemented via several different methods using triangulation: COO Cell of Origin: considers the location of the origin base station as the location of the caller. TOA Time of Arrival TDOA Time Difference of Arrival AOA Angle of Arrival E-OTD Enhanced Observed Time Difference

21 Mobile Positioning Technology Assisted GPS Approach The assisted GPS approach uses satellite-based and cellular-network based technology. It can achieve accurate location and still operate in area behind or under barriers.

22 Mobile Positioning Technology WI-FI- Based Approach When a mobile device connects to the internet via Wi-Fi, its location can be determined by the location of the Wi-fi hot spot. This method relies on A database of Wi-Fi hot spots Mobile device must be within 100m of Wi-Fi access point With Wi-Fi triangulation the accuracy can be higher Does not work when mobile device is out of range. Wi-Fi hot spots database must constantly be updated

23 Mobile Positioning Technology IP Address-Based Approach When a mobile device connects to the internet, the IP address of the mobile device, which is usually a gateway of the Internet Service Provider (ISP), can be used to determine the location of the mobile user. The accuracy of this approach is relatively low, usually within the range of a city area.

24 Mobile Applications- Technical Challenges Mobility comes at price. The small size of mobile devices imposes limitations: Limited System Resources(CPU, Memory, and Battery Power) Limited Bandwidth and Intermittent Network Connections Small Screen Size, Tiny Keyboard and Outdoor Environment

25 Mobile Application Development Mobile GIS can be developed using 3 main approaches. 1.Native Application Based Java,.NET Mobile, Java mobile etc. 2.Mobile Browser Based HTML, HTML5, XHTML, Javascript, Adobe Flash, Silverlight etc. 3.Message Based SMS, MMS etc.