The GIS industry and Web maps are on the verge of a revolution. Mobile is that revolution. Strong statements, but tracing the history; GIS applications first migrated from the desktop to the Web.
ESRI moved from ArcInfo, to ArcIMS and ArcGIS. On the Web Google introduced slippy maps and gobs of free data. Combining this with a plethora of new tools, Google opened the way to the development of cool new Web based mapping applications. New Web technologies appeared. Adobe released Flex, Microsoft Silverlight and AJAX became popular in the Javascript world. The dawn of rich Internet applications (RIA's) was upon us where Web apps looked and felt like desktop apps. An array of new free RIA API's appeared. ESRI released ArcGIS Javascript, Flex and Silverlight API's. In the open source world Open Layers and OpenScales became available.
So why will mobile have such a big impact? Two words; geo-location and context. Geo-location, or current GPS location, is fueling a new location based services industry. The likes of Foursquare, FaceBook and Yelp are allowing mobile users to discover who and what are near them. Extend that to geospatial and users can start any GIS query and discovery from their current location. Context provides increased insight. GIS has been traditionally used in an office or home. Taking these GIS applications into the field and running them on a mobile device, dramatically improves insight.
Mobile devices are beginning to impact many enterprises, and industry sectors. The geospatial sector with its focus on location will be particularly impacted. GIS applications written for an non-mobile experience will be extended, and enhanced. A slew of new tools will be developed taking advantage of geo-location and context. GIS will be integrated with other technologies. Ultimately the industry is facing massive new opportunities.
Figure 1: Flex ArcGIS Web Viewer
Mobile GIS Opportunities and Challenges
But before we get too far ahead of ourselves, mobile is young and still presents challenges. Hardware varies. Screen size is a particularly relevant variable for GIS application developers. Smartphone screens range from 2.1 to 4". Tablets from 7" to 10.1". More than just skinning an application for the screen size, apps need be designed with screen size in mind. For example, GIS viewers work well on tablets, but are near to impossible to use on a smartphone.
There are many mobile platforms. Apple have IOS, Google introduced Android, Microsoft with Windows and many others. Just like the old PC days with the competition between Windows and MAC, the field of mobile operating systems is many and varied. This directly impacts software. Mobiles access applications in one three ways. First there is access through a mobile browser. Second there is installing a native application on the device. Last there is installing a hybrid application. It gets confusing!
Let's discuss a hypothetical scenario to better understand this complexity. A client wishes to take an existing ArcGIS Web viewer, written in Adobe Flex, and make it accessible via any mobile tablet. Since its a Web application the most obvious, and cheapest approach, would be to access the app via the mobiles browser. True, but the client wanted the application accessible on ALL mobile tablets. Apple decided they would not support the Flash Player on the IPad. That means the Flex viewer would not be available on the IPad. The next option is a native application. All platforms have their own native languages, meaning languages which go hand in hand with the underlying operating system. In Apples case that is Objective-C. The Flex application could be rewritten in Objective-C and pushed out to the Apple App Store. That could be expensive. Add to that the need to write a version for Android, Windows etc and things get very pricey. The third option is to build a hybrid application. Adobe have just released Flash Builder 4.5.1, which allows a single AIR application to be installed and run on most mobile devices.
Hybrid Mobile ArcGIS AIR Apps
Hybrid seems potentially the most cost effective solution to satisfy this clients need. Webmapsolutions decided to put this to the test. They built a Flex ArcGIS application and attempted to port it to mobile AIR and install it on an IPad2. They included modified versions of widgets from the existing ESRI Flex 2.4 viewer in the application. The process proved almost seamless. The video in Figure 2 below shows the application running on an IPad2.
Figure 2: An ArcGIS AIR App Running on the IPad2
The only challenge proved to be widgets which contained components not yet supported in mobile AIR. The Layers widget was most notable, and a new widget needed to be built, one different to that in the Flex version of the app. The application was built using the new ArcGIS 2.4 Flex release, which has additional mobile support added. Flash Builder 4.5.1 also allowed the app to be compiled for Android and Blackberry.
Mobile GIS Opportunities
Hybrid AIR ArcGIS applications may well be the best current approach to building cross platform GIS solutions. Whether it be porting existing Flex applications to mobile, or building ArcGIS viewers from scratch. It is worth noting that Silverlight is also not supported on many mobile browsers. AIR may be a potential solution here too. AIR also comes with a light database, so if mobile access is lost local storage could be used, until connection is restored and upload can take place.
Design is a key consideration with mobile. No matter which approach is taken finger gestures are quite different mouse interaction. On screen interactive elements, such as buttons, need to be bigger. The best cross browser Web solution is Javascript. The HTML 5/ Javascript combination offers interesting longer term possibilities.
Mobile tablets are relatively new. They are about to make personal computers obsolete. Tablets will revolutionize the location based sector, which includes GIS. Geo-location and context added to the already powerful tools offered by GIS, present many opportunities to add to and extend geospatial solutions.
Additional Information
Link to video of ArcGIS AIR application running on an IPad 2:
WebMapSolutions are Web and mobile application developers.Specializing in locations based services (LBS), GIS and mapping applications. For more information:
