Question about phone wallet app

No it does not migrate.

You need to set it up on the new phone using your key words.

DO NOT delete your old phone until the wallet is up and running on your new one.

Either that or set up a fresh clean wallet on your new phone and send your Vet & VTHO to the new address...........obviously only do this if you don’t have a node.

When you create an address you receive a 12 word phrase - the mnemonic phrase. Those 12 words literally are your wallet. The address is a cryptographic representation of those words.

You can import that wallet to any device that can run the app with those 12 words. That’s why you have to keep them protected, safe and secure and ideally a couple of copies stored in multiple locations just in case the worst happens (fire/flood for example).