How do I send email on heroku using PHP?

Question

I have created PHP app and deployed using heroku. In the app, I have contact form to send mails to my gmail account. To implement this, I have written the following PHP code

Answer 1

Heroku doesnt allow send e-mails, you must use external SMTP server.

"To send emails from applications deployed to Heroku, use an external SMTP service." https://devcenter.heroku.com/articles/smtp

How to send e-mails throw SMTP is described here: Sending email with PHP from an SMTP server