This is a great topic and one that is near and dear to my heart. I love building software, but even more I like building valuable software that solves problems.

I'll share what's worked for me in the past and present, because I think context is important. What works for a b2b SaaS business at the early stage doesn't work for a later stage, larger services company. And vice versa.

Company A (a real estate brokerage with ~100 brokers and a customer service team):

I managed the tech team and worked on the product roadmap with CEO and COO. We set it quarterly.

* emails sent by the customer service team at crucial points (just after referring, after close, etc), including asking for reviews

* a chatbot on the website with the customer service team responding

* adhoc conversations the CEO had with customers and realtors.

Company B (startup, I was tech co-founder, B2B, SaaS):

Clean slate, co-founder had a research background and loved surveys.

* captive facebook group. This was great because this was a place to get feedback on the app and other issues facing our customers, but was also a great "offer", kinda like a whitepaper but more valuable. We could reach out to potential customers and offer them membership in the premier community of their peers for free. bonus!

* customer advisory board. I met with a few select customers once a month for an hour each time. Would get feedback on general usage, trends in their business, and had time to show them new features and discuss the roadmap.

* NPS survey: I installed delighted and we tracked that number over time.

* zendesk/intercom for tickets and chat.

Company C (funded startup, B2D/B2B, I joined, they pivoted):

Unique situation for me because when I joined they were still working on the business model, hence the pivot. Bigger team, I wasn't privy to the big picture.

* In app analytics. They had built out a way to see what customers were doing inside the app, so you could run queries and ask "is anyone using feature X", for example. I wasn't a common user of this, but it was interesting to run periodically.

* I filled a role for a little while doing customer research to help us as we pivoted. This consisted of trolling linkedin for connections with a certain profile, then scheduling calls to discuss their problems and how they were solving them. If appropriate, showing them a little demo. Recorded it all and wrote it up to share with the team.

* At this same company the CEO (post pivot) was a huge fan of having sales folks provide feedback from customers. I wasn't around to see how this turned out, but it made sense from an intellectual standpoint.

Company D (bootstrapped startup, B2D/B2B):

My current employer is unique in my experience because they have a product, it's multifaceted and can be used in many different ways (horizontal, not vertical), it's not entirely a SaaS offering, there's an intense focus on the security and privacy of our users, and they have both a community using the product for free and a customer base, paying for the product.

Here's where we get feedback from right now:

* web based forum. We use nodebb. Moved over from slack. We lost the community hangout feel when we did so, but gained: a lesser expectation of an immediate reply, permanence of questions and responses, SEO, searchability by users. I'll also use it as a lightweight doc repository where I can capture answers for questions asked elsewhere. If a question gets asked often enough in the forum, I'll promote it to the official docs. This feedback is more of the "this isn't working" type.

* zendesk and slack for paying customers. Again, "this isn't working"

* github issues. We provide templates for bug reports and feature requests. The community then votes on the feature requests and when we have time for new work, we sort by the number of upvotes and include that in our roadmap planning. Features are more "I wish the app did this" type of feedback.

* sales call feedback. This is adhoc, but valuable. I'd say the CEO aggregates this in his head and again the team uses it in our roadmap planning. This is more of the "we'd buy if it did X" type.

* email newsletters/drips: we have a couple of automated email drips after certain events (user signs up for newsletter, etc). Unsure what kind of feedback we get, but we always ask.

* ask for reviews on a site like capterra. We do this because it's a light ask for folks, helps get us feedback, and also helps with marketing.

* outreach and profiles: I have started to actively reach out to community members and customers and do interviews. These feed into marketing material (blog, case studies) but also inform the team about how folks use the software. This is time consuming but you can learn a lot about how people use this multifaceted tool in surprising ways.

* google analytics: goals have been set up for various actions and we track completions.

Taking a step back, I think the hard part is not collecting feedback (that's just putting in the work and there are tons of tools out there to help) but rather reifying it into an actionable roadmap and incorporate into company decisions. This is part of the role of a product manager, after all, and quite a valuable one.