I believe there are two kinds of marketing tools. One, that can help you with direct marketing, and others that can help you become a better brand (through speedy customer service or strong social media presence).
Indirect marketing tools:
1. ProProfs Help Desk
2. Buffer
Direct marketing tools:
3. BIGContacts
4. Qualaroo
5. Survey Monkey
I saw a YouTube video the other day by a SaaS guy where he broke down some helpful marketing strategies.
Here's the link:
Some of the ideas sound kinda cheesy, but who knows, maybe it works :)