When you use TradeGecko to email your customers you may see that the email was sent via TradeGecko. This happens when the email domain doesn't match the domain in the "From:" address.
For example if you send an email via TradeGecko using a gmail email address you will see the following:
The “via” field cannot be removed and appears depending on which email client you are using. Email Clients that will display the “via” field include:
If you are using iCloud the field will not appear, as seen below.