To add or replace a Primal in your party, just follow these easy steps:

• Tap the Settings icon in the top right corner (the one with the three lines).
     

• Select Party.
     

• Tap the Primal you want to remove. It will be highlighted with a white glow.

• Tap Switch.

• Your full roster will appear. Choose the Primal you'd like to replace it with.

• Tap Switch again to confirm your selection.