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Developing a GeoPackage mobile app to support field operations in agriculture

Authors:
Chen Zhang at George Mason University
Chen Zhang
Ziheng Sun at George Mason University
Ziheng Sun
Gil Heo at George Mason University
Gil Heo
Liping Di at George Mason University
Liping Di
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Abstract and Figures

GeoPackage, an open format for geospatial information, provides a gateway to bridge agricultural geographic information and mobile devices such as smartphones and tablets. In this paper, we present a Cordova framework based GeoPackage mobile application to support field operations in agriculture. By implementing GeoPackage SDK on mobile application, GeoPackage files can be easily accessed, managed, and visualized in field operation. Based on Cordova framework's powerful extensibility, the application can be run on multiple mobile platforms such as iOS, Android, and Windows Phone to meet requirement of clients using different types of mobile operating system.
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Developing a GeoPackage Mobile App to Support
Field Operations in Agriculture
Chen Zhang, Ziheng Sun, Gil Heo, Liping Di*, Li Lin
Center for Spatial Information Science and Systems
George Mason University
Fairfax, VA 22030, USA
czhang11@masonlive.gmu.edu, {zsun, gheo, *ldi}@gmu.edu, llin2@masonlive.gmu.edu
Abstract—GeoPackage, an open format for geospatial
information, provides a gateway to bridge agricultural
geographic information and mobile devices such as smartphones
and tablets. In this paper, we present a Cordova framework
based GeoPackage mobile application to support field operations
in agriculture. By implementing GeoPackage SDK on mobile
application, GeoPackage files can be easily accessed, managed,
and visualized in field operation. Based on Cordova framework’s
powerful extensibility, the application can be run on multiple
mobile platforms such as iOS, Android, and Windows Phone to
meet requirement of clients using different types of mobile
operating system.
Keywords—GeoPackage, Mobile application, Geospatial data,
Field operation
I. INTRODUCTION
With the rapid development of mobile devices in recent
years, smartphones and tablets have became a new generation
platform for geospatial data management and analysis.
Although conventional desktop workstation is still the major
tool in today’s GIS (Geographic Information System) field, the
swift widespread of smartphone significantly accelerated the
application of mobile geographic information system (mobile
GIS), which defined as the integration of GIS, GPS (Global
Position System), and RS (Remote Sensing) capability for
accessing geospatial data using mobile devices [1].
Comparing with the traditional mobile devices, new
generation of tablets and smartphones are equipped with
powerful hardwares such as high performance center
processing unit (CPU), mass storage memory, high resolution
touching screen and camera, G-sensor, GPS module,
fingerprint identification system. As the result of the
advancement of the hardware, mobile operating system, such
as iOS and Android, are developed as the next generation
platform for data management and analysis based on its
extraordinary portability and extensibility. According to the
statistics of the mobile applications availability, more than 1.6
million apps are available for downloading in Google Play and
more than 1.5 million apps are available for downloading in
Apple’s App Store by July 2015, and this number keeps
growing in exponent [2].
In modern agricultural activities, mobile device has became
a indispensable tool for supporting field operation. The
advancement of GPS and its wide application made mobile
device a useful tool for in situ collecting geospatial information
[3]. Simultaneously, the performance gap between mobile
devices and traditional desktop workstations has been
narrowed due to the quick development of mobile chip market.
For example, Apple A9 processor, the CPU of the latest iPhone
series products, comes with dual cores of which the clocking
speeds can be reached to 1.85 GHz. Qualcomm Snapdragon
820, an another mainstream processor towards to mobile
platform and mainly used on Android devices, is powered by
quad cores and its clocking speed can be up to incredible 2.2
GHz. Such powerful processors inside the smartphones make it
possible to process and analyze data in real time. Therefore,
based on the portability, functionality, and interoperability of
mobile devices, users will be allowed to access, manage,
analyze, visualize, and share many kinds of geospatial raster
and vector data in agricultural field operations using
smartphones or tablets anywhere and anytime. Imagine a small
powerful tool which can be held in the pocket and carried to
the field, such advantages will offer great benefits for millions
of agricultrual related users including farmers, researchers,
educators, students.
As a new open format for transfering geospatial
information, OGC (Open Geospatial Consortium) GeoPackage,
which characterized by standards-based, platform-independent,
portable, self-describing, and compact, provides a gateway to
bridge agricultural geographic information and mobile devices
[4]. Since pulished in 2014, GeoPackage has been widely
implemented by many major vendors and open source
packages including GDAL, Luciad, QGIS, Esri, NGA
(National Geospatial-Intellegence Agency), GeoServer, and
Safe Software.
In this paper, we developed a Cordova framework based
GeoPackage mobile application to support field operations in
agriculture. By implementing NGA GeoPackage Library on
mobile application, users can easily access, manage and
visulize the GeoPackage files in filed operation. Besides, to
meet the requirement of clients using different types of mobile
devices, we adopt Apache Cordova as the mobile application
development framework to wrap CSS, HTML, and JavaScript
code. Based on the powerful extensibility of Cordova
framework, the application can be run on multiple mobile
plarforms including iOS, Android, and Windows Phone.
II. RELATED WORK
Many mobile platform based projects and products are
accelerating the agricultural production and facilitating the
study in agriculture area. Different with the traditional desktop
workstation, mobile devices provide a more flexible way to
support agricultural field operation.
In 2012, Delgado, Kowalski, and Tebbe proposed the first
mobile application of the Nitrogen Index. The aim of this tool
is helping farmers to implement better nitrogen management
practice, increase nutrient use efficiencies at the field level,
lower impacts to the environment from nitrogen losses, and
achieve higher economic returns [5].
Geofairy, a multi platform mobile application operated by
Center for Spatial Information Science and Systems (CSISS),
George Mason Univeristy, was released to support field
operation in agriculture in 2014 [5]. As a hub of geospatial
informationto, Geofairy retrieves agricultural data from 8
source datasets with more than 100 data layers covering the
whole globe and provides different types of agricutural
information including weather, vegetation, elevation, soil
moisture, land cover, atmosphere and precipitation.
Lomotry, Chai, Jamal, and Deters initiated MobiCrop
project [7] as a mobile distributed system with a three-layered
deployment consists of mobile nodes, a cloud-hosted
middleware, and a cloud-hosted database. MobiCrop
application was desgined towards to iOS devices such as
iPhone and iPad which enable farmers to have mobile access to
make decisions on applying pesticedes.
In 2015, Ferreira, Vinhas, Bogossian, de Carvalho [3]
proposed TerraMobile App as an Android based mobile
application for geographical data gathering and validation in
fieldwork. As a case that implementing GeoPackage on mobile
devices, in TerraMobile App, the offline geofraphical data are
stored in OGC GeoPackage file. TerraMobile plugin was
developed to access and generate GeoPackage files, and the
file will be availbale through TerraMobile server.
III. FRAMEWORK
To implement OGC GeoPackage on mobile devices, we
adopt NGA GeoPackage libraries which provides the ability to
read, write, import, export, share, and manage GeoPackage
files. NGA GeoPackage Libraries is a series of open source
libraries including Java library, Android SDK, iOS SDK, and
JavaScript library.
As discussed in the section I, Android and iOS are two
major platforms in today’s mobile market. To implement
GeoPackage on Android and iOS based mobile devices, we can
choose Android SDK or iOS SDK which providing
GeoPackage functionalities and utilities to Android/iOS apps.
However, using Android SDK on iOS SDK makes the project
relying on platform-specific APIs, which means the process of
developing Android project and the iOS project are mutually
independent. To make the mobile application more flexible and
easier to be implemented across different mobile platforms, we
use Apache Cordova as the general framework for web-based
hybrid mobile application, which allow developers build
mobile applications using CSS3, HTML5, and JavaScript
instead of platform-specific APIs. On the other hand, we adopt
NGA GeoPackage JavaScript library, which provides
GeoPackage functionality and utilities to node and web
applications, as the major implementation library. The
architecture of GeoPackage mobile application is displayed as
Fig. 1.
Fig. 1. The architecture of GeoPackage mobile application
The architecture of the project consists of several parts: the
NGA GeoPackage JavaScript Library, Cordova Application,
and Mobile OS. Cordova Application, as the core component
of the architecture, consists of three major parts: Web App,
HTML Rendering Engine (WebView), and Cordova Plugins.
Among which, Web App interacts with NGA GeoPackage
JavaScript Library via JS APIs, HTML Rendering Engine and
Cordova Plugins interact with Mobile OS via iOS API,
Android API, and other platform-specific APIs such as
Windows Phone API, Firefox OS API, Ubuntu Touch API,
Blackberry OS API, and LG webOS API.
IV. EXPERIMENT
As shown in the Fig. 2, NGA provides an official open
source demo of the web application implementation of
GeoPackage JavaScript Library [8]. The interface of the NGA
GeoPackage JavaScript implementation demo consists of a
OpenLayers Map and a control panel, users can open
GeoPackage files from local disk or sample links then the data
will be displayed on OpenLayers .
Fig. 2. The interface of NGA GeoPackage JS Demo
Fig. 3. The interface of GeoPackage iOS app
Fig. 4. Reading GeoPackage files from cloud drive
Based on the architecture of the section III, we
implemented a Cordova based mobile application on iOS
mobile device using NGA GeoPackage JavaScript Demo. The
screenshot of the iOS app running on iPhone 6/iPhone 6s is
shown in Fig. 3 (the layout of the app may vary when the
resolution of the device has changed), we can see some
GeoPacakge data is loaded by turning on the switch button in
control panel on the right and displayed on the left. As the
basemap, OpenStreetMap covers the whole world with up-to-
date geographic information data, in this case, three
GeoPackage files “foul_sewer”, “a_manhole”, and
“surface_water_sewer” are displayed on the basemap.
To protect systems and user’s privacy, iOS limits the
privileges of all apps by “App Sandboxing” and users cannot
read GeoPackage files from any local path of local storage.
Alternatively, as shown in the Fig. 4, iOS allows user open
data from cloud drive such as iCloud Drive and OneDrive,
which provides an alternative way for reading user’s
GeoPacakge files.
V. CONCLUSION
In this paper, we present a Cordova framework based
GeoPackage mobile application to support field operations in
agriculture. By implementing GeoPackage SDK on mobile
application, users can easily access, manage and visualize
GeoPacakge files in field operation. Furthermore, the powerful
extensibility of Cordova framework makes the app performing
flexible on multiple mobile platforms including iOS, Android,
and Windows Phone. Experiment result shows the mobile
application implemented using our architecture provides an
approach to accelerate the field operation and facilitate the
study in agriculture area.
ACKNOWLEDGMENT
This work is supported by OGC Testbed 12, and partially
by grants from NSF EarthCube (Grant # ICER-1440294, PI:
Dr. Liping Di) and the U.S. Department of Energy (Grant #
DE-NA0001123, PI: Dr. Liping Di).
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[3] K. R. Ferreira, L. Vinhas, C. H. Bogossian, and A. F. A. de Carvalho,
"A mobile application for geographical data gathering and validation in
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[4] OGC. (2014). GeoPackage Encoding Standard [Online]. Available:
http://www.opengeospatial.org/
[5] J. A. Delgado, K. Kowalski, and C. Tebbe, "The first nitrogen index app
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http://ngageoint.github.io/geopackage-js
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Geofairy – A Mobile App Towards A Brand New Geospatial Information Sharing Mode Available: https://zihengsun.wordpress.comgeofairy-a-mobile-app- towards-a-brand-new-geospatial-information-sharing-mode
  • Jan 2014
  • Z Sun
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Number of apps available in leading app stores as of
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Geofairy -A Mobile App Towards A Brand New Geospatial Information Sharing Mode
  • Jan 2014
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Z. Sun. (2014). Geofairy -A Mobile App Towards A Brand New Geospatial Information Sharing Mode. Available: https://zihengsun.wordpress.com/2014/10/30/geofairy-a-mobile-apptowards-a-brand-new-geospatial-information-sharing-mode/
GeoPackage Encoding Standard
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