Should you need to switch between Accounts within the Swiftlane App on an iOS device, you will go to your Profile icon and hold down on the Profile icon and you will see a pop-up like below.
You can then see "Add Account +". Click "Add Account +"
Then you will be asked to sign in to add the Account:
You will be sent a verification code via email to enter.
Once you have entered the code click "Done"
Now you should be able to see the account details as below.
When you hold down the Profile icon again you should see the account you just added (see below)