This shouldn't be in the Bitcoin forum since it is about Ether which is an Altcoin. I suggest you move it to the Altcoin discussion board.
What benefits does that site offer compared to
https://etherscan.io/ for example? You enter your ETH address and whatever is stored in your wallet is displayed as part of your portfolio.
It's clearly not that useful if only need to check one address but if you have a whole wallet, like a passphrase or a hardware wallet many with addresses to check, then it could definitely be helpful.