If you look closely in Settings -> About, you can find your current version and your installer version.

Installer version will not increase when you auto-update, unlike the Current version. Your installer version will only increase when you install Obsidian with a new installer.

To grab the latest installer, please go to our official website.

Most features can be delivered by auto-updating, but to update the engine for certain new features Obsidian, we encourage you to grab the latest installer from our official website from time to time, when your current version is above the installer version by a lot, for example when your current version is 0.10.8 while installer version is 0.8.3.