Sometimes it is useful to find out what version of the app you have installed. You'll always want the newest version to benefit from the latest features and fixes.
There are two numbers that are important:
Finding each of these is detailed below...
The build number can be found in two places.
The login screen
The Profile screen (accessed via the More button then clicking your Profile)
To check you have the latest code-push, first click the more (...) button, then click the Preferences menu option.
Next use the Sync and Get Status buttons to check for updates and ensure that you're using the latest version (the Running and Found numbers should match).
Note that the app will ordinarily update automatically with small code updates (and when this happens you'll see the loading screen appear for a couple of seconds whilst the app refreshes). These buttons just provide a way to manually check the version number in case the code-push didn't apply automatically.
It is also worth ensuring that auto-updates are turned on for the App Store / Google Play for occasions when we perform a bigger release.