Need a smart contract to exchange ERC20 for Ether and Ether for ERC20.
The goal is, you send ether you get erc20, you send erc20 you get ether back. Without having to use web3 tools.
The only way I can think for implementation is to use the ERC20 itself as exchange contract.
Then the token address will have to hold both ether and its own tokens.
This sounds like bad practice, or is it? Any better idea to achieve that?