Polaris GPS Navigation

Polaris GPS Navigation

GPS 導航和離線地圖,適合遠足、航海和越野探險。

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歷史版本

Polaris GPS Navigation
Polaris GPS Navigation 9.25 APK
2024年02月05日 21.25 MB

Requires Android: Android 4.4+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 6ee82ea71498cd85dee94751a951c1f52737c49c

Size: 21.25 MB

What's New:

1. Find hiking and bike trails in your area or around any location.
Polaris GPS Navigation
Polaris GPS Navigation 9.24 APK
2023年09月30日 21.34 MB

Requires Android: Android 4.4+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 228285e385ec52346dc8dcfa01fccedfdddd9066

Size: 21.34 MB

What's New:

1. New features and themes, improvements and bug fixes.
Polaris GPS Navigation
Polaris GPS Navigation 9.23 APK
2022年03月20日 19.63 MB

Requires Android: Android 4.4+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 5a211dbcc3322292661ad1c45e09da28a3b6de63

Size: 19.63 MB

What's New:

1. New maps: Hiking and biking, National Geographic and others.
2. The Map It companion app is no longer required for location and waypoint searches.
3. Added boundaries and place labels to offline satellite maps so they are easier to use.
Polaris GPS Navigation
Polaris GPS Navigation 9.22 APK
2021年12月21日 19.45 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: b88a44c455b3cf575032937101915e5cc193c1db

Size: 19.45 MB

What's New:

1. Unlocked more waypoints and trails.
2. Energy optimizations: Uses less battery when connecting to internet for online services.
3. Minor bug fixes and optimizations.
Polaris GPS Navigation
Polaris GPS Navigation 9.21 APK
2021年09月30日 19.25 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 2146e3f5ee1f782a4322e40e09fe6d71ed6b274a

Size: 19.25 MB

What's New:

1. Bug fixes.
2. Improved support for external mbtiles map files.
3. Added Nautical Electronic Navigation Charts (ENC's for USA only). Older raster nautical charts are still available.
4. The most recent Android security features have been added.
Polaris GPS Navigation
Polaris GPS Navigation 9.20 APK
2021年09月29日 19.25 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 0ff8b0b592582c8d5185ba159190330cc86c36f8

Size: 19.25 MB

What's New:

1. Improved support for external mbtiles map files.
2. Added Nautical Electronic Navigation Charts (ENC's for USA only). Older raster nautical charts are still available.
3. The most recent Android security features have been added.
Polaris GPS Navigation
Polaris GPS Navigation 9.19 APK
2021年09月23日 19.24 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 4ee459dfd66f902a952f6821508f10b5f9acbce1

Size: 19.24 MB

What's New:

1. Improved support for external mbtiles map files.
2. Added Nautical Electronic Navigation Charts (ENC's for USA only). Older raster nautical charts are still available.
3. The most recent Android security features have been added.
Polaris GPS Navigation
Polaris GPS Navigation 9.18 APK
2021年07月16日 18.91 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 913e37d218d8e68b132999cb698cbd1bb8e6e3f1

Size: 18.91 MB

What's New:

1) Higher detail faster offline maps.
2) Added more options to customize maps.
3) Gyroscopic stabilization added to all magnetic compasses.
Polaris GPS Navigation
Polaris GPS Navigation 9.17 APK
2021年02月09日 18.91 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: f0620d9d57425a212ee043a5b3968bb2027a2865

Size: 18.91 MB

What's New:

Lots new in this release:
1) Updated map engines: Maps run faster, smoother and offer more features.
2) Vector maps updated to reflect the latest geographic information.
3) All maps may now operate in heading-up or north-up mode, controlled either by GPS or magnetically.
4) Gyroscopic stabilization added to all magnetic compasses.
5) Graphics and UI improvements.
Polaris GPS Navigation
Polaris GPS Navigation 9.16 APK
2020年11月11日 13.65 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: fa017a8d547930e892d4c41d55a4b178239e236b

Size: 13.65 MB

What's New:

1. New navigation satellite identification and locations map.
Polaris GPS Navigation
Polaris GPS Navigation 9.15 APK
2020年08月11日 13.51 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: c16035951ae00cffef68302eeb6b0f9cf08c2759

Size: 13.51 MB

What's New:

1. This is a critical update for NOAA Nautical Charts USA.
2. Efficiency improvements for raster map viewing and downloading.
Polaris GPS Navigation
Polaris GPS Navigation 9.14 APK
2020年08月05日 13.51 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 8f862ab962e6d887b23dca281da9f93f8151fcf2

Size: 13.51 MB

What's New:

Security improvements.
Optimizations for Android 9 and 10.
Polaris GPS Navigation
Polaris GPS Navigation 9.13 APK
2020年07月07日 13.51 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: abf45768c65932c478cf85f9f05933d891c004b8

Size: 13.51 MB

What's New:

Optimizations for Android 9 and 10.
Polaris GPS Navigation
Polaris GPS Navigation 9.12 APK
2020年05月30日 13.3 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: 409217962496df5c093b6a385aed3614ba06ff11

Size: 13.3 MB

What's New:

Optimizations for Android 9 and 10.
Polaris GPS Navigation
Polaris GPS Navigation 9.11 APK
2019年10月24日 12.65 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: b59a2df1a0c8cbca8053469fac0d50ef04e4c010

Size: 12.65 MB

What's New:

* Our most exciting update to Polaris in several years!
* All new set of maps with more on-map navigation tools and measurement methods.
* Many improvements on old features.
* Fully compatible with Android 10
Polaris GPS Navigation
Polaris GPS Navigation 9.10 APK
2019年10月12日 12.65 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, x86, x86_64

Screen DPI: nodpi

SHA1: aaa959f61630d9a3fd0f3d25eda50f1254ee9ad9

Size: 12.65 MB

What's New:

* Our most exciting update to Polaris in several years!
* All new set of maps with more on-map navigation tools and measurement methods.
* Many improvements on old features.
* Fully compatible with Android 10
Polaris GPS Navigation
Polaris GPS Navigation 9.07 APK
2019年08月01日 13.02 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, mips, x86, x86_64

Screen DPI: nodpi

SHA1: 7980b9857b89259aa042e6b60c54475367e6bbeb

Size: 13.02 MB

What's New:

V9.07:
Added volume controls to anchor alert.
Major enhancements and additions:
• Several raster maps, including the USGS Raster Set, are now available at higher resolution free for offline use.
• Measuring tools now on all map types.
• More information stored and reported with waypoints.
• Coordinate system swapping tool allows you to easily switch coordinate systems on-the-fly from any screen.
• Bug fixes and graphics reformatting.
• Set the maximum resolution of your downloaded raster maps.
Polaris GPS Navigation
Polaris GPS Navigation 9.06 APK
2019年06月06日 12.99 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, mips, x86, x86_64

Screen DPI: nodpi

SHA1: a15ce031b02c874c81f88268684ff39bdbd98e6d

Size: 12.99 MB

What's New:

V9.06:
Added privacy policy.
V9.05:
Major enhancements and additions:
• Several raster maps, including the USGS Raster Set, are now available at higher resolution free for offline use.
• Measuring tools now on all map types.
• More information stored and reported with waypoints.
• Coordinate system swapping tool allows you to easily switch coordinate systems on-the-fly from any screen.
• Bug fixes and graphics reformatting.
• Set the maximum resolution of your downloaded raster maps.
Polaris GPS Navigation
Polaris GPS Navigation 9.05 APK
2019年06月01日 12.95 MB

Requires Android: Android 4.0+

Architecture: arm64-v8a, armeabi-v7a, mips, x86, x86_64

Screen DPI: nodpi

SHA1: d77ad4ba51dd76e8dafd68eea919d197f6609aa7

Size: 12.95 MB

What's New:

V9.05:
Several new features and enhancements including:
• Measuring tools now available for all map types.
• More information stored and reported with waypoints.
• Coordinate system swapping tool allows you to easily switch coordinate systems on-the-fly from any screen.
• Some bug fixes and graphics reformatting.
Polaris GPS Navigation
Polaris GPS Navigation 8.67 APK
2018年10月10日 13.57 MB

Requires Android: Android 3.0+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 95525227e23333a967c40d625f72020d8df156da

Size: 13.57 MB

What's New:

V8.67
MINOR BUG FIXES
=====
Recent:
- ADD WAYPOINT INFO TO PHOTOS
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.66 APK
2018年09月21日 13.6 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 2fa5a69e4f8c7aec6407b88a844c9256970b7410

Size: 13.6 MB

What's New:

V8.66
EFFICIENCY IMPROVEMENTS - REMOVED SOME UNUSED LIBRARIES (ie Google Firebase).
=====
Recent:
- ADD WAYPOINT INFO TO PHOTOS
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.65 APK
2018年09月10日 13.71 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: a6f86dbe8ab615e23aa651d1b050e2adcbae5f10

Size: 13.71 MB

What's New:

V8.65
- Now includes option to add waypoint info to waypoint photos.
=====
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.64 APK
2018年07月07日 13.65 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: e9005622ea431bdff1896ed8e35cba58b7e0b607

Size: 13.65 MB

What's New:

V8.63 - MINOR GRAPHICS CHANGES
==
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.63 APK
2018年05月30日 13.68 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: b3ffa1fc2c581af5e450852fdbd1300b1cfb19e1

Size: 13.68 MB

What's New:

V8.63 - NEW FEATURE: DRAG ANCHOR / BOAT DRIFT ALERT
==
V8.62 - REQUIRED UPDATE FOR NON-GPS ALTITUDE SOURCES
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.62 APK
2018年05月24日 13.56 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: b1e91fd0919c353296084091680219e6a313e054

Size: 13.56 MB

What's New:

V8.62 - Required update for non-GPS altitude sources
==
V8.56
- British OSGR & OSGB-36 DATUM
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.61 APK
2018年03月21日 13.53 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: d2c879503e3f32682199e276b05bc7621cea732a

Size: 13.53 MB

What's New:

V8.61 - ENHANCEMENTS FOR TALL SKINNY SCREENS (Galaxy S7, S8, S9 and others).
==
V8.56
- British OSGR & OSGB-36 DATUM
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.60 APK
2017年11月14日 13.52 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: ee63c2ade7be13dbf7865598e8b09e5b069fe370

Size: 13.52 MB

What's New:

V8.60 - BUG FIX FOR JELLYBEAN PHONES AND LOWER
==
V8.56
- British OSGR & OSGB-36 DATUM
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.59 APK
2017年10月24日 13.51 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 332b483eae1b9f264a9b555419a594ead8509cb0

Size: 13.51 MB

What's New:

V8.59 - ADDED MOON PHASE AND MOON TIMES REPORTING TO SUNRISE-SUNSET SCREEN.
==
V8.56
- British OSGR & OSGB-36 DATUM
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.58 APK
2017年07月13日 13.33 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 8f5c33cbe55e2ef40df4b1ce68cb24286864adaa

Size: 13.33 MB

What's New:

V8.58
- Bug Fix for short GLONASS NMEA sentences
==
V8.56
- British OSGR & OSGB-36 DATUM
V8.54
- NEW TOPO MAP
V8.51
- REQUIRED TO ACCESS NOAA NAUTICAL CHARTS.
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.57 APK
2017年06月06日 13.2 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: ebf0f2742de722a2f3536b1a95228dc335c6caaf

Size: 13.2 MB

What's New:

V8.57
- Bug Fix for missing library on some devices
==
V8.56
- British OSGR & OSGB-36 DATUM
V8.54
- NEW TOPO MAP
V8.51
- REQUIRED TO ACCESS NOAA NAUTICAL CHARTS.
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.56 APK
2017年05月09日 13.2 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 96c70ba99f3230dac0b156df714cb160392c024a

Size: 13.2 MB

What's New:

** Added support for British Ordnance Survey Grid Reference and the OSGB-36 DATUM **
====
V8.54
- NEW TOPO MAP
V8.51
- REQUIRED TO ACCESS NOAA NAUTICAL CHARTS.
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation
Polaris GPS Navigation
Polaris GPS Navigation 8.55 APK
2017年05月07日 13.12 MB

Requires Android: Android 2.3.4+

Architecture: arm64-v8a, armeabi-v7a, mips, x86

Screen DPI: nodpi

SHA1: 0d6c41b6f4e2febddafe626bf1430fe77d82806a

Size: 13.12 MB

What's New:

** Added support for British Ordnance Survey Grid Reference and the OSGB-36 DATUM **
====
V8.54
- NEW TOPO MAP
V8.51
- REQUIRED TO ACCESS NOAA NAUTICAL CHARTS.
V.8.49
- MAP MANAGER FOR OFFLINE RASTER MAPS
- NO LIMITS ON VECTOR MAPS
V.8.20- NOAA MARINE CHARTS
V.7.80- USGS TOPO MAPS
V.7.72- FIND HIKING TRAILS, CAMPGROUNDS...
V.7.60- MAP LIBRARY FOR OFFLINE NAVIGATION
V.7.40- TRAIL ALTITUDE PROFILES
V.7.31- DRIVING DIRECTIONS
V.7.12- DRAW A TRAIL
v.4.90- MGRS coordinates
v.4.50- Marine navigation