On your Walgreens Premium Activity Tracker
Swipe to the left of the time/date screen to select "apps", then scroll to the second apps screen to select the settings icon (looks like a gear). Swipe to "info" and tap to select, and then swipe to see the SW xx.xx screen.
In the Striiv App
Tap the gear icon on the gray device banner found at the top of the app home screen, then scroll down to select 'Debug Info' to see the software version.