You have to add an ICS file to your submission email.
1) Go to the participant module -> Mailings -> Calendar items.
2) Choose 'Add Calendar item' and fill in the screen.
3) You can add the calendar item to all emails in this conference, also in the abstract module.
In the example we will add it to the submission mail of the participant module.
Go to the participant module -> Mailings -> edit the submission email.
4) You will see the calendar items option. Please check the box(es) of the item(s) you want to attach to the email.
5) Send a preview email to yourself to test it.
You can also forward the mail to your hotmail/gmail/yahoo to see if you can save it in your phone calendar.