Google's GMail SMTP server is a free service for anyone who has a GMail account. You can use this free SMTP server to send emails from your favourite web application.
If you don’t have a GMail account, you can create one at the GMail account creation page.
Then all you need to do is configure your mail client to use GMail for outgoing mail server. The details you should use are:
Outgoing Mail (SMTP) Server: smtp.gmail.com
Use Authentication: Yes
Use Secure Connection: Yes (this can be TLS or SSL depending on your mail client)
Username: your GMail account, i.e. firstname.lastname@example.org
Password: your GMail password
Port: 465 or 587
In case you use Google Apps with your domain name and you have created email accounts inside, you should use email account with the Username: field, i.e. email@example.com
The same email settings can be used with the email functionality of website application such as Joomla, PrestaShop etc. If you have any troubles configuring your website applications with the above settings you can contact the SiteGround Technical Support team and they will be glad to assist you.