Comparison of what you can do with just email hosting (e.g. POP, IMAP, and SMTP) vs. email hosting plus Mobile Sync.

General

Feature Email Email+Mobile Sync
Check email
Send Email
Address book, Calendar, Task, and Notes synchrnoization
Notes synchronization needs to be supported by the mobile device. Currently, this includes iOS7+ (e.g. iPhone and iPad) and Blackberry 10+.
Push email updates
Without Push Email, email is checked manually, or polled or performed using IMAP IDLE (if supported by the device supports). These methods can drain battery-life much faster. It often updates your device more slowly than push.

Device Support

Feature Email Email+Mobile Sync
Outlook v2013+ for Windows
*
IMAP for email access is best suited for Outlook 2013+. MobileSync of email is not supported in Outlook due to bugs in Outlook; however, MobileSync can synchronize your calendars, contacts, and tasks.
Apple iOS: iPhone/iPad/iPod Touch
Android
BlackBerry v10+ (natively)
BlackBerry old versions (with the purchase of a separate App)
Windows Mobile
Palm Pre/Pixi, Nokie, N900
Any Device with Exchange ActiveSync (EAS) support

Security

Feature Email Email+Mobile Sync
HIPAA-compliant? available
Remote Wipe
Without MobileSync, you can still setup remote wipe using a Google App (on Android) or Apple iCloud (on iOS).
Non-Blackberry HIPAA-Secure Outbound Email?
BlackBerry HIPAA-Secure Outbound Email?
SSL/TLS for Email Transport?
SSL/TLS for Calendar/Contact/Task Data Transport?

Speed and Synchronization

Feature Email Email+Mobile Sync
Battery Life maximized
Unlimited devices?
Shared account usage OK as long as the sharees are themselves licensed users.
Synchronize multiple accounts to the same device (if supported by device)
Real-time push updates for calendars, task lists, and address books
Real-time, two-way synchronization of calendars, task lists, notes, and address books?
Synchronization of any number of calendars, task lists, notes, and address books?
Multi-user access to shared calendars, task lists, and address books?
New email to phone within 1 minute of arrival
Access to all email folders?
Can poll for new email or check manually if Push is not desired.
Check email without using IMAP or POP on your mobile device?
Send email without using SMTP on your mobile device?
Customizable From Name/Address for sent email?
From Name/Address for sent email can dynamically match the To address?
Sending messages is subject to your account's normal daily and monthly limits on messages, recipients, and bandwidth usage.
 
   

Legend

Feature included

Feature not available.

Maybe. Depends on the exact features present in your mobile device's email program.

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