How do I set up my Openprovider email account on an iPhone or iPad?

To set up your Openprovider email on an iPhone or iPad, follow these steps:
Using configuration file
Log into https://mail.op-email.eu with your email account and it's password.
Under Mailbox tab, click on the Email link next to Apple connection profile. This will download the configuration file.
Manual Setup
Go to Settings > Mail > Accounts > Add Account.
Select "Other" and choose "Add Mail Account".
Enter your name, full email address, password, and a description for your account.
Choose IMAP or Exchange as the account type and enter the server settings: 
Incoming Mail Server (IMAP): mail.op-email.eu, Port: 993 (SSL)
Outgoing Mail Server (SMTP): mail.op-email.eu, Port: 587 (TLS/STARTTLS).