As far as I understand, my bitcoin [..] are somewhere in the big block chain and are not bound to a specific app.
This is correct, what is held within your app is the private key that allows you to spend the bitcoins held at that key's address. Without the key, the coins cannot be spent.
So, to make the bitcoins accessible in your blockchain.info wallet, you can do one of two things:
- Send a bitcoin transaction using bread, to a receiving address generated by your blockchain.info wallet.
- Import your bread wallet into blockchain.info, by inputting the bread wallet seed phrase or private keys into the blockchain wallet. Doing this will copy the keys held in your bread wallet, effectively creating two instances of the wallet instead of just one.
I don't know your exact reasoning or circumstance for switching wallets, but for what its worth, I like the security model used by bread much more than the one used by blockchain.info. At any rate, make sure your seed phrase is stored in a secure place!