When you have an email address that receives a high volume of emails from prospects whom you'd like to add as contacts in your web application, email forwarding does the job for you. By simply auto-forwarding all the emails that get sent to your email address (such as a contact us address or a sales address) to your web application's email address (firstname.lastname@example.org), you can have the senders of the emails added as contacts and also have their emails associated with their records in the web application.
Here's how you do it,
Login to the web application as an Administrator.
Go to Admin Settings > Incoming Emails.
In the Incoming Emails page, you can find your web application's email address. Click Copy to copy this address to your clipboard.
Next, log in to your email account. Below are the steps for auto-forwarding emails from Gmail.
Login to your Gmail account.
Click the Settings dropdown and choose Settings.
Click the Forwarding and POP/IMAP tab.
Click the Add a forwarding address button. In the popup that appears, paste your copied web application's email address.
Click Next to continue. You'll be asked to confirm the forwarding email.
Click Proceed to confirm the email forwarding.
Ensure that the radio button next to 'Forward a copy of incoming mail to' is enabled and the setting is saved.