Every blockchain on the market relies on a community consensus to verify the balance of each account on that blockchain. Therefore every wallet on the blockchain has a wallet balance that can be verified by anyone.
Most cryptocurrencies use what is called a blockchain explorer to search the balances of a particular wallet. In Apollo the blockchain explorer is incorporated into the actual wallet allowing seamless verification of balances when needed.
Although you can view the balance of a wallet you must enter in its passphrase to perform any action within the wallet, this means that all of your funds, assets, tokens, aliases are completely safe.