I am a big fan of Digital Marketer and recently on their blog they published eleven tricks to help increase open rates and engagement. Trust me they would know.
SOURCE: http://www.digitalmarketer.com/email-marketing-tricks/
Check these out. Most of them can be easily achieved with Interspire Email Marketer.
They do suggest sending email based on the recipients time zone… and that is something that Interspire cannot do out of the gate… maybe we should develop something?
Check it out!
Jacob