GPS Smartphone navigation just got easier using Geospatial PDF, an extension to Adobe’s Portable Document Format that let’s you encode GPS features with PDF documents. Imagine being able to download a PDF map to your phone for a state park or ski resort and having the ability to find your location or map a track on it using your phone’s built-in GPS capability. This is easier to do today than you probably realize.
Below, I show you have you can use Caltopo (a web-based navigation planning tool) to self-publish a Geospatial PDF map and the free trial version of Avenza Maps, a Smartphone app available for the iPhone and Android, to plot your GPS position. You can transfer the PDF map to Avenza by attaching it to an email message and opening it directly into Avenza on your phone. It’s really easy, as I illustrate below. Caltopo and Avenza are not the only mapping and GPS tools that support Geospatial PDF, but the versions I use in the example below are FREE, so you can try them out.
Who else publishes GeoPDF maps? All current and historic USGS quads (the entire USA) are available for free. Your tax dollars at work!
Step 1: Create a Geospatial PDF Map with Caltopo.com
Open Caltopo.com and find an area near you using the search function. You don’t have to plot a route or anything. Print a map of the area, selecting the “Geospatial PDF” format in the upper left hand corner. This adds some geo-reference information to the PDF document. Position the red focus window over the area you want to turn into a PDF and click on the button on the bottom of the Caltopo.com screen that says “Generate PDF.” Caltopo will generate a PDF document that will open in another browser window. Save this document on your computer.
Step 2: Open the Geospatial PDF map attached to an email message in Avenza Maps.
Step 3: Open the map in Avenza and plot your current GPS position.
To plot your current position in Avenza, click on the leftmost icon on the bottom of the screen, which will display a blue dot (above) showing your current position. It’s as simple as that! The position function also works offline, even when your phone is not connected to a cell phone or data network.
Avenza has some other nice features that you can use with your PDF map, including the ability to record a GPS track on your PDF map. Check out the middle and right photo at the top of this post: they show the track of the route I took on a ski tour in the area of the map generated for this example.
Geospatial PDF and the Future of Map Publishing
Geospatial PDF has the ability to completely transform the map publishing landscape that we know today, making it possible to publish ‘smart maps’ that can determine your location when displayed on a smartphone. The fact that geo-data is encoded in the PDF file makes it truly portable between devices, unlike the maps published by Garmin, for instance, which will only work on their proprietary GPS units and in their proprietary planning and publication tools.
The availability of free map publishing tools like Caltopo that can generate Geospatial PDF means that individuals can begin to self-publish smartphone-enabled maps for sale or to share with friends. The possibilities are really endless and should herald a new era of smartphone-enabled map publishing.
Written 2017. Updated 2018.SectionHiker is reader-supported. We independently research, test, and rate the best products. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.
I’ve found that importing the PDF from the web link is really quick as well, skipping dropbox entirely. Too bad Avenza sucks and jacked their prices beyond what is reasonable. You can still import 3 maps for free though.
After reading this comment and Philip’s review, I’m a little confused. What do people pay for on Avenza? As I stated below, I’ve used it free for 2 years on every hike importing many files.
For my purposes, if I want to upload more than 3 of my own maps, you need to pay $30 per year. I’ll pass on paying, as have many others judging by their ratings.
This is exactly what I do when abandoned national forest trails are shown on USGS quads but not on printed maps at stores. I trace my route on Caltopo USGS or FS 2016 maps, send the KML to email, and import the KML onto a free USGS quad. That way Avenza is always free, no need to worry about PDF purchases. I’ve been doing this on Avenza for 2 years at no cost, importing KML from other GPS tracks or Caltopo KML I made myself.
Caltopo maps loaded on Avenza on an iPhone 7 Plus has become my standard (with map and compass backup, of course). The geospatial PDF extension has been around for a while now – it came in with the PDF 1.7 spec (~2006) and Acrobat 8 (~2009). It is becoming more available to the consumer space as apps like Avenza are offering cheaper non-commercial use licenses that can take advantage of geospatial PDFs.
With their last major update, Avenza quietly introduced a limit of 3 uploaded maps on their individual non-commercial licenses (no limit on maps purchased from the Avenza store). If you want to load more but don’t want to go the Dropbox route, you don’t need to buy the $130 professional version Avenza license. There is an option to upgrade an individual, non-commercial annual license to allow for unlimited uploaded maps for $30 in the app. You need to do a little digging to find it though. (Please hold the “I’m not renting software!” rants. I have no connection to Avenza and software as a service seems to be the way the industry is going…)
An alternative to Dropbox as a means of loading Caltopo maps is to use the scanner tool in Avenza to scan the QR code on your Caltopo map (scan right off of your monitor screen) or just enter the associated Caltopo map URL directly.
A price I was happy to pay to be honest. $30 bucks is worth it for the flexibility.
As was I. (I don’t get the whole software should be free mindset that a lot of people seem to have. I don’t work for free and I don’t expect software developers to do so either.) I do think there will be more options available for using georeferenced PDFs as time goes on, but for now, $30 a year is pretty small compared to the annual outdoors budget! I also subscribe to Caltopo, more as a means of showing some support than needing the advanced features. I’ve been a professional geologist for a long time and its really exciting to see professional grade mapping and navigation tools becoming available to the recreational market at reasonable prices.
Likewise – I’ve looked at Avenza Map Publisher which costs thousands, when I can do a lot of the same with Caltopo. Not as pretty, but pretty dam good!
Timely article, for me anyway. We just attempted a bushwhack up a mountain in the Adirondacks a few weekends ago and used Avenza on my with a GPS enabled map. It worked great, much better than our bushwhack did :-).
My son-in-law does was able to create a map for me this time, but using Caltopo will allow me to get them myself moving forward. Just got introduced to Caltopo by this blog also!
Good to know via the comment from John that you can get the app for $30, because I noticed the limitation on just 3 BYO maps. I know that $30 is not chicken feed, but to be honest I have dropped a lot more cash than that on other hiking/camping gear that has no where near the impact on being successful and safe.
That $30 is per year, not lifetime. That’s pretty steep IMO
Yes, that is a different story – $30 per year. I already have a SPOT subscription to keep my wife’s piece of mind when I hike solo. I am not sure I understand what Zachary comment actually means, but I wonder if you are willing to just keep 3 or less maps on your phone, would you be able to add one any time (as long as it is not #4). It looks like you can delete them from Avenza. So with it being as easy as using Caltopo to create the map, I would just be willing to remove one from a previous hike.
How many maps do you actually need….exactly. the 3 map limit is perfectly workable.
Agreed. I was just not sure if once you crossed the threshold, even removing a map would let you add one later. I put three on mine and tried to load the fourth and it took me to the upgrade popup. So I went back and removed one map, and then I was able to add the new map keeping me at 3. To be honest, for my use I would only need the map loaded during the hike, no need to retain after.
That’s why I like to use Dropbox as my import conduit instead of a web link from Caltopo. It give me the ability to archive my old maps.
I only use USGS quads, which are free PDF downloads in the Avenza map store. You can search any area and download the quads, multiple years are available. I either used existing GPS tracks and create KML files, or I custom draw tracks on Caltopo and export as KML. Then I add KML files to Avenza using Import Map Feature on a free USGS quad
It seems like ya’ll are creating and importing custom Caltopo PDF maps instead of using existing or created GPS-KML tracks. I know I’m not crazy, I just imported 4 KML files onto 1 USGS PDF map for free. These 4 KML files were 4 separate GPX tracks from recent hikes. I also imported a KML I drew on Caltopo just now. I wish I could attach pictures.
I rarely draw tracks in Caltopo before a hike and use the maps it generates like GPS-enabled maps. What Caltopo gives me that’s not in the USGS quads is many different additional layers and additional maps that have different info than found on the USGS quads.
Since the USGS and FS maps are free, I’ve downloaded every quad for the mountains of NC, VA, and TN. Over 120 maps currently. I pin every relevant trailhead and waterfall, and label it. I also use Avenza for navigation in national forests when my Google Maps stop working. It’s easy to follow the forest roads on the USGS quad to a pinned trailhead or trying to find your way out on confusing roads.
I use the national geographic one that is totally free …
but can you import geospatial PDF’s? Test it and please let us know if it does
I am just trying to get a handle on this stuff but when I was Googling I found the National Park Service uses this type of format for their of PDF. I don’t even have a viewer yet on my phone but maybe someone more experienced could use this. But if you can’t zoom in the viewer, then it will be useless on a small screen.
Apparently, they use this to communicate recent incidents (like fire) info to multiple users on in a device independent way. Obviously, I have a lot more reading to do…
Zooming matters a lot less than being able to draw contour lines at a smaller interval.
As an FYI – Caltopo was developed for SAR.
This is all very cool. I learn things here I would never know about otherwise. Thank you for all the time and effort you put into this stuff.
I don’t really know it unless I can explain it. Know what I mean? Writing about it helps me too.
What are your thoughts about using a phone on a weeklong trip? How do you recharge? I use a GPS with waypoints for an additional navigation tool, but the screen is too small to actually read the map. Therefore the idea of a larger phone screen is appealing, but I don’t want to carry a phone and a charger.
I carry a battery, but mostly I know how to read and use a paper map without a GPS.
I use GaiaGPS with my iphone for the last year and have been very happy. One time $20 cost for the app and I can download any maps for free – in the U.S anyway. I keep the entire white mountains of NH in phone memory.
+1 for gaia
Gaia is great – I use it all the time, but there is a pretty steep learning curve. I like braking newbies in with PDF maps or Maplets because they are so easy to use. You don’t have to know anything about navigation to use them. Then if they want more, we open the firehose and turn them onto Gaia. But I really am not a fan of the web-based Gaia-GPS web portal. Caltopo is much more “open” and easy to use imho.
GaiaGPS is not $20 per year. The premium version that allows overlays, etc. is $40 per year.
Typo: GaiaGPS is “now” $20 per year.
It may seem silly, but I don’t quite get the point? I use openstreetmap data for the maps and a convenient website for the track, generating kml-files with the waypoints.
The kml files can be imported to wherever, in my case the maps.me app on android. If I don’t have a track yet, the OSM-data are downloadable and stored on-device.
Where’s the point of having a PDF of it?
Can you print a KML map? That’s just one of the reasons PDF is nice.
I don’t understand why this is not giving me the print option on the Cal topple map on my iPhone 6, but it’s working just fine with my iPad? Using Safari on both, it just won’t detect my location using my iPhone. Weird. I have all location services turned on.
Not sure what your doing. Are you viewing the map in the Avenza app? Doesn’t sound like It.
Step one of your instructions above says to create a geospatial PDF map using Cal topo.com. When I try and do that I don’t get the print option on my iphone but I do on my iPad. Which is weird. That’s all I’m trying to figure out. The rest of it works on my iPad. But not step one of your instructions above says to create a geospatial PDF map using Cal topo.com. When I try and do that I don’t get the print option on my phone but I do on my iPad. Which is weird. That’s all I’m trying to figure out. The rest of it works my iPad. But not fun phone.
Caltopo is very difficult to use without a big screen. I can’t get it to work on an iPad. Never tried a phone.
I’m very lazy and what I really want is for my GPS phone to always show me my location on any USGS topo wherever I am, without any network connection, without any trip preplanning nor any predownloading. I’ve gotten close to this by doing a one-time bulk download of all the USGS topos of my state and neighboring areas to a SD card, converting them to geotiff and putting the SD card in my phone and using Avenza import. Then in the field I still have to find out which quad I happen to be in using the state index map, then import the quad off the SD card. This takes a minute or so. If would be great if there was an app that would just automatically track my position and show it on the quad that I happen to be in.
Displaying GeoPDF also works now in the open source OruxMaps. I have tried it successfully with maps exported from CalTopo. There is no store, but also there seems to be no restriction on how many maps can be imported.
Just a question, why the app unable to detect coordinates when I import the PDF map using my iOS device.
Make sure your privacy is off and location services on.
Avenza will not load onto my iPhone 6. Is there another map app that will let me down load a PDF map? I just signed on to be an AT Corridor Monitor, and it would be so helpful to be able to down load the map I was given. Thanks for any help.
Not that I know of.