You'll choose to move your assets when you want to transfer your tokens from one chain to another.
For example, you may have $OSMO in Cosmo Hub and you want to transfer them to Osmosis.
Click on [Send] & Select [Move your assets]
Choose the type of tokens & chain you want to operate with
Enter the amount
You can select the amount in USD or in tokens by tapping on the double arrow
Select the sending and destination chains
Review the transaction fees
Click on [Continue] twice
Review your transfer details and click on [Continue]
Select [Confirm], continue and [Approve] in the Keplr pop-up
Once the transaction is complete, you'll be able to see the summary of the transaction
It's recommended to keep some available balance per chain to cover transaction fees