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Viewing high resolution maps on a mobile device overlaid with current GPS position

I've created a great high-resolution map of a block of land using Maps Made Easy, and downloaded all the technical files.

Now what I want to do is view this map on my iPhone and see my realtime GPS position on it, so as I walk around the property I can see on the map where I am in relation to the entire block.

The reason I want to do this is to find the exact property boundaries, which in some places are in extremely rugged places and concealed by overgrowth.

Google Maps or Google Earth are obvious apps on the iPhone which can show my current position on a satelite map, but the resolution is not good enough, and I can't find a way to use my high-resolution MME map with these. Also, even opening the map as a JPG on the iPhone is not possible due to its huge size.

Are there any solutions for doing what I want to do?

Nico Gianniotis

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If you "Enable Public Measurement Tools" in the Sharing section of the Map Detail page and then view the sharable URL you can hit the current location button and it will show your currently location with updates. 

Zane 0 votes
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Thanks. I think this is perfect, awesome. I will try it out.

I also found another forum topic regarding using MME with Google Earth (here). In it, it explains how you can open the 3D Google Earth KMZ file made by MME in Google Earth and see the MME map overlaid onto Google Earth's terrain map. The feature works fine with Google Earth on my laptop, but I wasn't able to successfully open the KMZ file in Google Earth on my iPhone.

Nico Gianniotis 0 votes
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Nice. That is another way to do it that I hadn't though of. The KMZs sometimes have trouble opening in Google Earth on a computer, let alone a mobile device. The models are only roughly 10MB but it seems take a lot of resources to open. You could also try opening the GeoTiff if the map isn't too big. 

Zane 0 votes
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I tried using the "current location" feature but unfortunately it didn't work very well for me. Something was screwed up with getting precise location for a wesbite inside a browser.

I am using an iPhone 14 Pro Max with iOS 16.4, and I tried with both Safari and Chrome browsers. The issue was the website was just not able to get my location reliably or accurately. It took many attempts before the blue location marker was even close to where I was, and then, it would not track me as I moved. 

To check whether the problem was the iPhone, I opened Google Maps and it was able to get my exact position instantly and also track in realtime me as I moved around. Of course, Google Maps is a native iOS app and probably has a different API for Location Services than, say, a browser like Safari or Chrome. 

It seems like it should have worked, but unfortunately, it didn't.

Nico Gianniotis 0 votes
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On a related note: regarding loading the 3D Google Earth KMZ file into Google Earth: is it possible for MME to produce a 2D version of this KMZ? I find the 3D interpolation a little off. I like to turn the Terrain layer off in Google Earth sometimes to view a purely 2D projection. I'm also finding it very difficult to get the altitude of the 3D KMZ file (which I am tweaking manually to look right) to match exactly with Google Earth's opinion as to the terrain altitude.

The attached screenshot shows the challenge: the 2D area outlined in red with yellow pins (in the lower part of the screen) represents a 2D topographical survey map. The high-resolution 3D part that is "floating" above it is the MME 3D KMZ layer, manually tweaked to altitude 130m Absolute.

What I'd love to see is a better registration of the survey map on the MME map. Sorry if my terminology is wrong, I'm a bit of a newbie at this :-)

Nico Gianniotis 0 votes
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Make sure you are not on WiFi and that your device has a solid GPS fix. It works great for me on my iPhone in Safari and Chrome. Maybe even turn WiFi off since that is sometimes used to derive location and it can be WAY off. 

Sometimes the height on the KMZ needs to be adjusted (especially if you don't use a ground reference image). There are LOTS of posts about this here:

https://support.dronesmadeeasy.com/hc/en-us/search?utf8=%E2%9C%93&query=kmz+altitude&commit=Search

The 2D version of the KMZ is the GeoTiff. 

Zane 0 votes
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OK, will try with WiFi off next time. As mentioned however other apps like Google Maps and Google Earth were getting my precise location and tracking it in realtime with the same conditions the browser was having trouble with. Might just be an iOS glitch.

Regarding the 2D version of the KMZ, the GeoTiff. I reduced it in size to 25% and added it as an Image Overlay feature in Google Earth (on laptop). Works great, however, I had to position and scale it manually to match GE's terrain, which was fiddly and felt inaccurate. There are EXIF tags in the GeoTiff, wondering if there is a way of automatically scaling and positioning it in GE using these geo tags? 

Now looking for a way to get that GeoTiff into the iPhone version of Google Earth...

Will follow up on the KMZ Altitude links, thx.

Nico Gianniotis 0 votes
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UPDATE: have just discovered when I scaled the GeoTiff to 25% all the GeoTiff tags were destroyed. Am now looking for a way to scale GeoTiff while preserving the geo tags...

UPDATE2: I used GDAL_translate to resize the full-scale GeoTiff, preserving the geo tags. Then I figured out the correct way to load a GeoTiff into Google Earth, and discovered I didn't even need to resize it to 25%. Even though the MME GeoTiff is > 2GB, GE is now giving me the option to create a Super Overlay, Scale or Crop. Not sure why this didn't work originally but all good now.

Nico Gianniotis 0 votes
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Nice. Thanks for the update and documenting your path so others can try to duplicate it if needed.

Zane 0 votes
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