POP3 or IMAP?
It’s not just a matter of preference, it’s about how you use your email. POP3 is an older protocol that came about before the new mobile revolution and is not suitable for this new mobile world. However, that doesn’t mean it’s not the right solution for you.

Why use POP3?
POP3 is a good solution when you want to access your email on a desktop and ONLY that desktop. If you only want to access your email server on a single computer, POP3 is really the way you want to go. This is a good option for businesses, because when you use POP3, you open your email program. It downloads all the new emails from Cap Rock and saves them to your computer. Pop3 than removes those emails from the server and stores them on your local machine. Pop3 is good when you have lots of email and you don’t need to share it on multiple devices.

Why use IMAP?
IMAP is a more modern protocol as it is a syncing protocol. This is beneficial for people that have a smartphone as well as a computer, and they need access to their email from multiple devices. IMAP synchronizes all changes on the server and not the local device, treating the email server — NOT your local computer — as the primary place your email is stored.
For example, if you access an email account with 100 unread emails with IMAP, you can access them instantly. They don’t actually download until you open them. Email attachments don’t download until you view them. When you open an email, it’s instantly marked as read on your device, the IMAP server, and every other IMAP client you use. If you organize your emails into folders, your organization will be synced online. If you delete an email, it will be deleted everywhere — not just on your local device.

Whether or not you use IMAP on your PC or laptop, IMAP should be used on your smartphones and tablets.