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Putting maps onto SD card of Backcountry Navigator #4501
Back To Discussion List Written: 2015.12.20 by: Robin Tivy

As you may know, Backcountry Navigator (BCNav) is the $12 app that I have on my Samsung Galaxy S4 phone, that lets me download the 1;50,000 maps and use the phone as a GPS when in remote areas. By default BC Navigator puts all the cached map files into the main storage area of the phone, not the SD card. They are in a data folder called BCNav. This is the default. However, over the past few months, I've got most of SW British Columbia loaded on my phone and I was running out of space. I had about 5 GB of maps. So I decided to move the entire "BCNav" data folder to my SD card which has 32 gigabytes.

So I used the phone's file manager to move all the files to the SD card using the file manager. It took a long time. Once you've moved that folder, you must configure BCNav "Storage Root" so it points to the correct location. And as it turns out, I couldn't point to the location where I put the BCNav folder. Android now forces such data folders to go in a certain place. The folder where it must go is a long and complex folder name. The folder must be under the following:

/mnt/extSdCard/data/com.crittermap.backcountrynavigator.licence/files

But I didn't know this, and was struggling to get it to work when the following message came up: (I painstakingly typed it all out below for you). Just for the record, I have Android 4.5 and Backcountry Navigator 6.0.1.

IMPORTANT MESSAGE FOR ANDROID VERSION 4.4 EXTERNAL STORAGE
 If you have changed your storage root (an advanced setting) to use an external card before the Android 4.4 update, you may experience severe problems since android decided to lock apps out of most of the external card in that update.

To correct this situation:

 1. Go to storage root settings and choose a recommended setting.
 The resulting path will be something like /mnt/extSDCard/data/com.crittermap.backcountrynavigator.licence/files or something equally long and difficult.

 2. Use My files, another file explorer app, or your desktop computer to move the BCNav folder from /mnt/extSdcard to /mnt/extSdCard/data/com.crittermap.backcountrynavigator.licence/files, or equivalent.

 3. Restart your phone and BC Nav PLEASE NOTE: Files stored in the recommended location are subject to removal on uninstall, so back them up. This is the only option, however, that we can offer for using external cards on 4.4.

Analysis: Note that the folder they recommend is as follows:
/mnt/extSdCard/data/com.crittermap.backcountrynavigator.licence/files

  FOLLOWING INSTRUCTIONS
 I followed the above instructions.

  1. First I changed the setting in BCNav program as follows:
     - I went into Settings..Storage Options..Storage Root(advanced) I then picked the awkward folder name as recommended above.

  2. Use File Manager to move the BCNav folder to:

     All Files..SD Card..Android..Data..com.critterm..ator.licence..files..BCNav

Comments

#6153 - 2017.12.22 Robin Tivy - Speed problem when on SD card?
For the past year, I've been putting up with incredibly slow delete speeds when erasing larger Gpx20 files. Eg: Around Mount Steele, 20 km is 146 points and 82 tracks. It would often take several minutes to delete the tracks, which was painful because I frequently load in new gpx20 files.

Tonight I discovered that by putting in a new SD Card, I got a huge increase in speed. I'm not sure if this is because the new card is faster, or because the old card was corrupted or something. The new card is a AData Premier UHS-I Class 10 card, 64 GB. The old SD card was a Kingston Micro 32 GB. (I'm not sure if the old card supported the UHS-I.

I should have done this a long time ago, but I was always worried that changing cards would be complex due to having configured things to use the card. But it turned out simple. I was able to just swap the cards with no issues. (Of course it doesn't move the data around, it just starts fresh on the new card. (To move the data, you'd have to use the file manager, as noted in previous discussion).

To do the actual card swap without confusing the phone was to temporarily change the storage location to "Internal", then turn off the phone, swap the SD cards, start phone back up and change the storage location to the new card. Here are detailed steps:
 

  1. Change storage root
     Menu.. Settings.. Storage Options.. Storage Root (Advanced) This brings up a screen which shows that my External Storage was on the horrendous licence folder previously noted:
      /storage/extSdCard/Android
      /Data/com.crittermap.backcountrynavigator.licence/files

  2. select [x] Internal Storage
     (which is the following:
     storage/emulated/0

  3. Turn off the phone and swap the SD Cards

  4. Change storage location to point at new card

I then tested the speed by going to Mount Steele, and clicking the gpx20 link. That is 20 km in radius and includes 146 waypoints and 82 tracks.

Loading was half a minute before all the waypoints and tracks appeared. But delete only took a few seconds for the 146 waypoints and 82 tracks.

Conclusions: My old card was much much slower. Perhaps it was corrupted, because I think only half the space was used.

Interesting Note: When I swapped the cards, I went in with the "My Files" file manager to the SD card, and I noticed that the structure of my music folders was on the new SD Card. "RT_MP3" and under that Linda Ronstadt. But no files. So somehow the main unit must remember folder struture of the card?