Accessing log files

If you want to look into the history of your game in detail (especially useful for figuring out variant unlocks), you might want to look at (and share) your log file.  This is a text file that lists every event in the game, in plain english.  It includes a lot of redundancy, so it may not be EASY to read, but the information is all there.

Finding log files by system:

STEAM/Windows:
C:\Users\<USERNAME>\AppData\LocalLow\Handelabra Games Inc_\Sentinels

iOs:
This is a little complicated, because Apple doesn't like people looking at files
* Download a copy of iExplorer from here: https://www.macroplant.com/iexplorer/
(It looks like running in demo mode is fine if this is all you're using the program for, so you probably needn't buy a registration code).
* Go to Apps -> Sentinels -> Documents.
* Right-click on log.txt and select "Export to Folder..."

Android:
Android/data/com.handelabra.Sentinels/files/log.txt

Moderators, is this worth making sticky?

As near as I can tell, on Android it's at:

Android/data/com.handelabra.Sentinels/files

There's a file called log-copy.txt

Just a quick correction.  For Android, I think you actually want log.txt  It looks like log-copy.txt is a copy of the log created for games that have been continued.