Yes. Gmail/Yahoo/Hotmail allow users to add other email accounts. You will be able to check your domain emails at their web site besides your gmail and yahoo emails. You can also send email from your email address under your domain but such sending will need to send through our mail server. Gmail/Yahoo will ask you to provide our SMTP sending setting if you want to send email from your own domain instead of your gmail/yahoo address.

The following is the Youtube video teaching you how to add other email accounts to Gmail:

https://www.youtube.com/watch?v=4sWnKHLFwg8 

The following is the Youtube video teaching you how to add other email accounts to Yahoo:

https://www.youtube.com/watch?v=zh5eoiI14lA

1) Add Your Domain Email to Gmail/Yahoo/Hotmail:

POP server: pop.dnsexit.com

POP Port:   110 

Username:   is your full email address in lower case

Password:   is the password you assign to the email when creating it.

2) Sending from Your Domain Email Address settings:

SMTP server: mail.dnsexit.com

SMTP Port:   587 or 2525 

Username:   is your full email address in lower case

Password:   is the password you assign to the email when creating it.

Bear in mind that our SMTP server only allow sending from the same email address. Support you have a domain mydomain.com with us and you setup 2 emails under it, say info@mydomain.com and help@mydomain.com. If you want to send email from info@mydomain.com, you will need to use the authentication for info@mydomain.com to send. If you use the auth for info@mydomain.com to send emails for help@mydomain.com, it will reject the sending.