Attempting to pull a single file using
adb pull /data/data/com.corp.appName/files/myFile.txt myFile.txt
fails with
failed
On MacOSX, by combining the answers from Calaf and Ollie Ford, the following worked for me.
On the command line (be sure adb is in your path, mine was at ~/Library/Android/sdk/platform-tools/adb) and with your android device plugged in and in USB debugging mode, run:
adb backup -f backup com.mypackage.myapp
Your android device will ask you for permission to backup your data. Select "BACKUP MY DATA"
Wait a few moments.
The file backup will appear in the directory where you ran adb.
Now run:
dd if=backup bs=1 skip=24 | python -c "import zlib,sys;sys.stdout.write(zlib.decompress(sys.stdin.read()))" > backup.tar
Now you'll you have a backup.tar file you can untar like this:
tar xvf backup.tar
And see all the files stored by your application.