dApp Builder is a platform to create Ethereum dApps from prebuilt smart contracts (no coding) and instantly deploy them to blockchain...
Try the test dApp, which receives messages from users and saves them in the blockchain. You can browse messages, sent by other users, and send yours. For sending messages to a smart-contract, you need to pay ETH for gas, required for sending the transaction. The dApp works in Rinkeby Test Network. You can receive ethers for your wallet here for free by using Crypto faucet.