MOBILE LOCATION-BASED APPS. Lecture in University of Tartu Jaak Laineste,

Transcription

1 MOBILE LOCATION-BASED APPS Lecture in University of Tartu Jaak Laineste,

2 Part 1 LOCATION-BASED SERVICE OVERVIEW

3 Jaak Laineste GIS/LBS experience 17 years in GIS/mapping, 12 years in LBS Mobile operator LBS in all over the world Nutiteq since 2006 Nutiteq and mobile development Part of Mobi Solutions group since 2009 J2ME, Android, BlackBerry, iphone teams Naval navigation apps

4 Location-Based Services 1. Location-based: 80% of data 2. Service (or mobile application) 3. Mobile technologies (phones, networks) 4. Mobile positioning LBS is a technology, not application type Can be aspect of any application type

5 Two meanings of LBS Classical definition: Mobile Positioning MPS Mobile operators User Interface: SMS, Web, WAP, USSD, IVR Today s LBS : Smartphones with GPS, tablets mobile apps, web services, HTML5 Google Maps, PND, Check-ins, Google Now

6 Operator-based LBS Mobile Positioning Find location using mobile network Works with any mobile, no requirements Accuracy with Cell-ID: 300m km (~1 km avg) Operator can also use in-phone GPS with A-GPS Only operator can do it, Can give to trusted 3rd party Typical services FriendFinder, Games Find Nearest SMS Fleet Management Recent trends Operators open APIs, including location There are aggregators: e.g. LocationLabs, Loc-Aid Location-based advertising (EMT, Estonia)

7 Popular LBS apps in smartphones Navigation Tomtom, Navigon, Garmin, Nokia maps etc. Also Waze Business around you Reviews, events, classifieds etc Yelp, Loopt, Qype, Zvents, Eventful, Opentable etc Transit and traffic info US, West Europe Trapster speed camera warnings Social: Facebook checkins Games: Foursquare Sports trackers: Runkeeper, Endomondo

8 Un-successful applications Friend tracking Track & publish my location Location-based advertising Location-based alerts Augmented reality (with maps)

9 Hard problems GPS takes too much battery GPS coverage and accuracy is bad No indoors Maps are limited No indoors No walking level Real user needs are hard to estimate

10 Successful apps Local is local Content is the king, but expensive Understand topic pymwymi There is no killer app but you can create killer service Location is just a technology Not the core differentiator

11 Part 2 GIS INTRODUCTION

12 GIS definition Geographic With geographical dimension Information System Software, servers, computers Wikipedia: a system designed to capture, store, manipulate, analyze, manage, and present all types of geographically referenced data. In the simplest terms, GIS is the merging of cartography, statistical analysis, and database technology

13 Started in early 1970 ies Key companies, drivers ESRI, Intergraph, MapInfo, AutoDesk, Oracle Universities Key focus Desktop-GIS special GIS tools Servers, client-server model Expensive, specialized, heavy Recent developments (from late 90ies) OGC standards: WMS, WFS, GML etc Cloud-based, mobile Classic GIS

14 Neo-geography Web/Internet-based Easy to use Cloud services Cool startups GeoIQ, CartoDB, OpenGeo, MapBox, GISCloud Free commercial tools Google: Maps, Earth, SketchUp, FusionTables etc Yahoo, Microsoft Bing, MapQuest Open source software OSGeo.org: server, desktop, web Open sourced data OpenStreetMap

15 Mobile LBS future trends Augmented Reality Issue: mobile sensors Needs powerful image processing 3D 3D earth (2.5D) Buildings, textures etc Apple ios 6 Maps 360-degree view Issue: bandwidth Walking/local/indoor maps Issue: content update is expensive Your ideas!

16 GIS TECHNOLOGY AND DEVELOPMENT

17 Why special approach Data is quite complex Two-dimensional (or 3D, 4D) Complex relations Nice visualization is processing-hungry Base maps Big datasets, different features Specific map data Dynamic, can be big etc

18 A lot of data in a single screen Type 4 bytes Name 100 bytes Point on map 16 bytes Base map 32+ KB 27 relations 205 ways (lines) 1920 points (x 16 b) Checkins 4 bytes People 4 bytes

19 Geo basics Data models vector raster other Coordinates Projections, coordinate systems

20 Data models Raster PNG for maps, lossless JPG for aerials GeoTIFF, coverages Key parameters: bitmap resolution, size Vector Base objects: points, lines, polygons Collections: multi-point, multi-line, multi-polygon Attributes (fields): text/boolean/numeric/binary etc Texts on map - labels from attributes Layer same as table in DB Special cases: topological models, graphs

21 GIS Layers

22 Other data models Elevation models DEM Digital Elevation Model TIN - triangulated irregular network 3D worlds Collada, X3D Google Earth Warehouse Point clouds Lidar laser measurements

23 Hillshade from DEM

24 TIN

25 Point cloud

26 3D model

27 GIS layers simplified One base layer Background map: Google, OpenStreetMap etc Raster-based Overlay layer(s) Points of Interest, markers GPS location dynamic info Lines, Polygons Clustered points

28 Demo Quantum GIS with vector in action Open vector data layers Styling map

29 QGIS with OSM data

30 Display map Request data for bounding box (BBOX) Reprojection (if needed) Show set of layers Style data colors, symbols etc Different map zooms have different data Geocoding address to coordinates Reverse-geocoding Find nearest neighbour(s) Find objects in radius (buffer) Calculate distance between objects Find Point in area (polygon) Routing find optimal path in graph Clustering - show big datasets on map Typical vector data operations

31 Common GIS Data formats Shapefile (ESRI) most common 4-5 files per layer:.shp,.dbf etc One geometry type per layer allowed No style information, pure geometry Optional projection file.prj KML (Google, open standard) Vector data, includes styles Special data types: 3D data (Collada), linked data, visual coverages Can have only WGS84 coordinates Can be KMZ zipped file Other formats SpatiaLite: vector and raster data. Any projection, no styles. Text files with coordinates or addresses Every commercial GIS has own format(s) Free converter:

32 Spatial SQL database basics Special column data types(s): Geometry, Point, Polygon... Geographical indexing Usually R-Tree, based on object bounds (bbox) Geographical functions: Manipulations, relations, queries etc etc Metadata table: Defines coordinate system, data type for every Geometry column

33 Geometry primitives in WKT (2D)

34 Multipart geometries in WKT (2D)

35 PROJECTIONS

36 Coordinate systems Geographical spherical Units: Latitude and Longitude Based on an ellipsoid, e.g. WGS-84 Datums, also WGS84 for GPS DMS for display, decimal degrees for programming Projected - cartesian Units: usually meters (can be km, miles) Hundreds of named projections, mostly for local regions Reduce distortions: keep angles, distances, areas equal

37 Geographical coordinate space

38 Cartesian (projected) coordinate space

39 Different projections The Globe Applet Check out some Oblique Mercator, Cassini, Rectangular Polyconic Common in real life Plate Carre, Mercator, Spherical Mercator, UTM, Lambert Conformal Conic (in L-EST)

40 Short and long projection description EPSG codes: EPSG:4326 WGS84 EPSG:3301 Estonian system EPSG:3587 Google web Was also EPSG: <EPSG:3301> PROJCS["Estonian Coordinate System of 1997", GEOGCS["EST97", DATUM["Estonia_1997", SPHEROID["GRS 1980", , , AUTHORITY["EPSG","7019"]], TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG","6180"]], PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]], UNIT["degree", , AUTHORITY["EPSG","9122"]], AUTHORITY["EPSG","4180"]], UNIT["metre",1, AUTHORITY["EPSG","9001"]], PROJECTION["Lambert_Conformal_Conic_2SP"], PARAMETER["standard_parallel_1", ], PARAMETER["standard_parallel_2",58], PARAMETER["latitude_of_origin", ], PARAMETER["central_meridian",24], PARAMETER["false_easting",500000], PARAMETER["false_northing", ], AUTHORITY["EPSG","3301"], AXIS["Y",EAST], AXIS["X",NORTH]]

41

42 Coordinates as QR-Code GEO: ,

43 MAP DATA SOURCES

44 Web maps Google Maps Javascript, Flash, Static APIs, Earth 3D Geocoding and Directions (routing) services Mobile APIs: Android, iphone Bing Maps Web, Mobile API (WP7, iphone) Nokia Ovi Maps Web, Mobile (Qt, J2ME)

45 Web map restrictions Technical restrictions Cannot be restyled, no visual customization Limited to provided API-s, feature limits Can t get map data, or even images Some mobile platforms not served at all Commercial limits Some services (e.g. Navigation) require special license Advertising is added

46 Commercial map data Global vendors Vector: Navteq (Nokia), TeleAtlas (TomTom), AND Aerial/Satellite: DigitalGlobe, Blom ASA... Local vendors Regio, Maa-amet In almost every country, more detailed to globals Specifics Technically quite flexible Usually quite expensive

47 OpenStreetMap (OSM) Free and open data Vector data in 2D Streets, roads, buildings, amenities etc A lot of services Map images (tiles), geocoders, routers etc Special views: opencyclemap, openpistemap etc Everyone can improve the map in Estonian

48 Potlatch2 web-based OSM editor

49 JOSM OSM main editor

50

51 OSM advantages Free and open to use No advertising, restrictions Vector data access Custom styles for mapping Own filters of data on map (layers) Interactive data overlays (POI layers) Advanced services: routing, search, analysis Fast and easy updates Find error go fix it yourself! Note: follow community guidelines

52 GIS TOOLS

53 Main OGC standards WMS Web Mapping Service Send coordinates in URL, get map image WFS Web Feature Service Send coordinates in URL, get vector data as GML WFS-T enables writing to server GML Geography Markup Language XML-based Specific schemas depending on application TMS Tiled Map Service Get 256x256-pixel map images for x, y, zoom Others GeoRSS RSS with geotags Geo EXIF GPS tags for digital photos

54 OCG

55 Free GIS tools Desktop tools mapping, analysis, processing Quantum GIS (QGIS) udig, OpenJUMP, gvsig GRASS analysis Google Earth - view/create KML Google SketchUp create 3D models Databases Data sharing/storage Analytical queries, eg. count points in regions PostGIS Postgres add-on. Pgrouting PostGIS Raster (in next version) Processing GDAL/OGR raster and vector library, command-line converters

56 Free GIS tools for developers JTS Java Topology Suite, ports in C etc Lot of complex algorithms, geometries, graphs, geographical indexes Proj.4 C-based, has few ports Hundreds of predefined projections SpatiaLite SQLite extension, for files Also some raster features PostGIS Postgres SQL server extension for vector Raster features in next version

57 Web Mapping GeoServer: WMS, WFS, WCS, caching MapServer: WMS, TMS, WFS MapGuide OS Mapnik: TMS, OSM TileMill: good for on-line styling Web Processing Services Degree etc Developer toolkits OpenLayers Javascript GeoMajas Java-based MapFish Python-based Cooperation project: Free GIS Servers

58 Google Fusion Tables General data table API service Very basic geo-features GeoCommons.com Nice maps and analyses, a lot of content shared No editing, content for US mostly GISCloud.com Also server-based editing is possible Not very mature OpenStreetMap Only for community-created data Content requirements: verifyable objects etc CartoDB.com closed beta now Hosted GIS servers Free GeoWebServices

59 Build your own geodatabase When you need own server: Requirements are very different Cannot customize readymade servers Specific use cases: user permissions etc Using OSGeo tools Database: PostGIS Web maps: eg MapServer Client tools: Geomajas, OpenLayers Using OSM toolkit Web maps: PostGIS + Mapnik API/data management: Rails_port (ruby), Postgres Client-side modification: JOSM, Potlatch2 etc

60 WEB MAPPING DEVELOPENT IN SHORT

61 General model Server-side Google, Bing, OpenStreetMap etc etc Map content is already there for free Tile-, WMS or vector based API Client-side JavaScript, Flash, Silverlight, plug-in or HTML API Bundled with server: Google, Bing etc OpenSource: OpenLayers

62 Tiled map server Bing sample

63 Web mapping client API - OpenLayers <script> function init() { map = new OpenLayers.Map("basicMap"); var mapnik = new OpenLayers.Layer.OSM(); map.addlayer(mapnik); map.setcenter(new OpenLayers.LonLat(13.41,52.52) // Center of the map.transform( new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984 new OpenLayers.Projection("EPSG:900913") // to Spherical Mercator Projection ), 15 // Zoom level ); } </script>

64 OpenLayers add marker... var lonlat = new OpenLayers.LonLat( , ).transform( new OpenLayers.Projection("EPSG:4326"), // transform from WGS 1984 map.getprojectionobject() // to Spherical Mercator Projection ); var markers = new OpenLayers.Layer.Markers( "Markers" ); map.addlayer(markers); markers.addmarker(new OpenLayers.Marker(lonLat));

65 Web mapping server APIs WMS view-based s/alus-geo?service=wms &VERSION=1.1.1 &REQUEST=GetMap &LAYERS=HALDUSPIIRID,BAAS KAART &STYLES=default &SRS=EPSG:4326 &BBOX=26.7,58.3,26.8,58.4 &WIDTH=600 &HEIGHT=600 &FORMAT=image/png& TMS tile-based /13/4702/2451.png /13/4703/2451.png /13/4704/2451.png /13/4702/2452.png /13/4703/2452.png /13/4704/2452.png...

66 WMS image response 26.8E,58.4N 600px 26.7E,58.3N 600px

67 OSM Tile-based map: zoom 13 X Y

68 Tiles or WMS? Tile advantages Can be cached in client Can be pre-rendered in server Can be preloaded to client Faster, suitable for high-traffic services WMS advantages Supports selection of projection, layers, styles Smaller number of requests Suitable for high flexibility services (GIS apps)

69 MOBILE LBS APP DESIGN TIPS

70 Bad UX design Long alphabetical listings, no search Example: RMK Android app Ignore geographical dimension Mobile apps are used out in a wild Too many points on map Clusters group points Filters show minimal number Assume user GPS location User is maybe planning to go there Assume always network connectivity Unoptimized user experience LBS must be more robust than average mobile app (eg game) It is probably not used just to kill some tome

71 Common technical mistakes Geographical data handled as non-geographical Using place names / addresses to find nearest Use just two float fields for geographical objects Cannot be indexed, can t use existing geotools Ignore GPS specifics Location fix takes long time: 20 sec to 20 min Fix is not always available: indoors etc GPS kills the battery! Coordinate system errors mix degrees/meters, projections swap x/y

72 ANDROID APPS WITH LOCATION

73 Location determination Plain GPS Free satellite signal requires 4 satellites min. Accuracy: ~5 meters Time to first fix (TFF) up to 20 minutes AGPS Assisted by network TFF ~20-30 sec Claimed to have also better sensibility Network-based locations Immediate but less accurate Mobile network cell (Cell-ID) ~1 km error average, can be 10 km Wifi location: ~100 m accuracy Cell/Wifi databases: user-collected. Google, Skyhook, Apple, Nokia, OpenCellID etc Hybrid method First give quick inaccurate network location, then try GPS Used in Android, iphone

74 Location API in Android Location Method Selected automatically based on set requirements: Cell-id,WiFI or GPS Features Listen for updates most common Last known location (cached) not suggested Proximity alerts not guaranteed Best strategy depends on app

75 Mobile mapping main platforms Smartphone platforms Most have GPS and good screen iphone Bundled Apple MapKit, Apple Maps. Opensource: Route-me Android Bundled Google MapView, Google Maps OpenSource tools: Osmand, Nutiteq etc Windows Phone 7/8 Bing maps SDK, Nokia Maps SDK OpenStreetMap coming?

76 GPS : not guaranteed BlackBerry BB Maps, Nutiteq SDK Nokia Symbian and Meego Nokia Maps, Qt-based Nokia S40 Nokia Maps SDK, Nutiteq Samsung Bada decarta SDK Mobile mapping other platforms

77 Mapping SDKs on Android Raster-based Google Maps API no offline, routing, license limits Nutiteq SDK offline, multi-platform. GPL+commercial OSMDroid LGPL, Android-specific Vector-based Mapsforge GPL, only offline, nice rendering Droyd SDK also navigation, only offline Ericsson Maps online data, ugly rendering 3D Earth solutions Glob3 Mobile in development, BSD license HTML5 OpenLayers Mobile OpenWebGlobe WebGL based 3D earth

78 Display map MapView API interactive map: Google Maps, 2D, online Add clickable points to map (annotations) Add overlays (rasters) Show user GPS location Geocoding android.location.geocoder API, online Reverse-geocoding android.location.geocoder getfromlocation() Find nearest neighbour(s) Find objects in radius (buffer) Depends on data source Calculate distance between objects Location.distanceTo() method Find Point in area (and other georelations) Spatial-enabled GIS engine: PostGIS in server or Spatialite in phone Routing find optimal path in graph Google online API, other on-line routing engines Spatialite routing, in small area Point Clustering Typical geotasks in Android

79 Other useful free tools for mobile Spatialite = SQLite + GEO Big datasets (8M objects DB) Spatial operators, e.g. distance, nearest... Requires NDK/JNI. Prebuilt binary in bitbucket.org/nutiteq/android-map-samples/... JTS Java Topology Suite Java-level spatial graphs, operators, geometries Free GIS tools processing/preview data See above

80 Nutiteq 3D Android Maps SDK Mapping Number of pre-defined map sources, OpenStreetMap default Custom map sources, you can define own tile API On-line and off-line mapping (prepackaged, stored, cached) 3D support 2.5D views 3D models: KMZ/OpenCollada Other features Points of Interest (POI) on map (layers, individual places) Polygons and lines on map Raster map overlays Vector layers

81 Do it yourself speed camera warning Speed camera alerts on Android Shows map, gets GPS location, reads data, plays alerts Tools Nutiteq Mapping SDK nutiteq.github.com/hellomap3d Content POIPlaza.com data file OSM maps (online or offline) Alarm audio mp3 file Bonus points Add a 3D driving car from Monster Milktruck as your location Speeding alerts from current speed

82 Thank you! Jaak Laineste CEO, Nutiteq