Sitecore 9+ ships with EXM, a powerful Email Marketing tool that can put XDB data to work.
Since Sitecore XP 9.0 Initial release, EXM has been a part of the platform rather than an additional module. This has gone a long way to help EXM not become the long lost forgotten cousin of the Sitecore world.
Unfortunately, there are some fairly impactful issues with the earlier releases that may warrant a minor upgrade, rather than fighting the platform. 9.0 Update 2 and above have appeared to be much more stable….the more recent the better!
Sitecore has released a cumulative hotfix for 9.0 Update 1 that addresses many significant (ie. blocking!) issues, rolled into a single package. We had great success after implementing it (even without an upgrade). As always, check with support if it’s right for your solution!
However, if you’re utilising Azure search, it’s still highly recommend upgrading to at least 9.0 Update 2 as it does introduce the ability to rebuild your xdb index. Simply put, earlier versions do not support this when using Azure search (Solr is fine). While not specifically an EXM issue, it does rely heavily on accurate and timely xdb data. Not being ale to rebuild the index may at some point get you in a very sticky situation when dispatching emails.
While out of the box for the 9.0.x series versions, there needs to be some additional love…EXM is so powerful it is absolutely worth it.