Your device database and logs are are stored in a dedicated area in your $HOME, the .jocala directory. Any data stored in the .jocala directory is preserved during a re-install or upgrade.
The internal files stored are:
Windows:
/Users/[userid]/AppData/Roaming/.jocala/adblink.db
/Users/[userid]/AppData/Roaming/.jocala/adblink.log
OS X:
/Users/[userid]/.jocala/adblink.db
/Users/[userid]/.jocala/adblink.log
Linux:
/home/[userid]/.jocala/adblink.db
/home/[userid]/.jocala/adblink.log
Note the leading dot in .jocala. Under Unix/Linux systems, the dot makes the directory hidden. Under Windows, the AppData directory is hidden by the OS, but dot directories are visible.
If you are upgrading from adbLink 2.4 or greater, you can copy your existing db and log files to the .jocala directory.
For adbLink 2.4 - 3.0, adbLink's internal files were stored differently.
Windows stored db and log files in the [installation] directory.
Mac/Linux stored db and log files in the adbfiles directory, alongside the binary.
For Mac, right-click on adbLink.app and browse Contents/MacOS/ to open the adbfiles folder in Finder.