Customizing fees when sending ETH
When you create a transaction on the Ethereum network using the Bitcoin.com Wallet, you can customize the fee you pay to Ethereum miners for sending ETH. Here's how:
On the "Enter send amount" screen, tap on the "Network fee" icon at the bottom-left
Choose from one of the three following options:
'Eco' means you'll pay a lower fee, but your transaction will take longer*
'Fast' strikes the optimal balance between cost and speed
'Fastest' optimizes for speed over cost
*Note that if you choose the 'Eco' option, there's a small chance your transaction will be canceled due to network congestion. In this case, you won't lose ETH (or pay fees), but you'll need to wait for the transaction to be canceled and re-initiate the sending process.
How do fees work when sending ETH?
Just like with Bitcoin, making transactions on the Ethereum network incur fees that are paid to miners. Also just like with Bitcoin, miners optimize for profitability. This means transactions with higher fees are typically confirmed faster than those with lower fees.
While transactions in Bitcoin are measured in size (bytes), transactions on the Ethereum network are measured by computational effort, which is delineated in units of "gas." For example, sending ETH from one wallet to another (one of the simplest transactions you can make on the Ethereum network), may consume 20,000 units of gas. More complicated transactions require more gas. If your transaction involves interacting with several smart contracts, for instance, you may consume 100,000 gas units or more.
When you create an Ethereum transaction, you need to indicate the amount of gas you're willing to consume. This is your "gas limit." Any gas that isn't consumed by the transaction will be returned to your wallet. However, it's possible to consume gas without a transaction confirmation. This is a notable difference from the Bitcoin network, where you can't be charged unless a transaction goes through.
The other factor you need to consider when you create an Ethereum transaction is the "gas price," which is the amount of ETH you are willing to pay for each unit of gas consumed. Gas price is measured in Gwei (giga wei), which itself is a denomination of ETH. Each Gwei is equal to 0.000000001 ETH (10-9 ETH). So, instead of saying that your gas costs 0.000000001 ETH, you can say your gas costs 1 Gwei.
The cost you pay for a transaction on the Ethereum network, then, is a function of the gas price you set and the gas units your transaction consumes. As described above, both of these parameters are customizable using the Bitcoin.com Wallet.