You can add and remove multiple items from your policy when you first set it up and purchase in the app.
If you wish to add items to an active policy you can also add them through the app. Go to "Individual Items", and select "Add another item".
Please note that if you have an active discount, you won't be able to do this in-app. You'll need contact support by using the in-app messaging, call customer support at 034 5241 2563, or email [email protected].