We use Customer.io! It's quite nice, but I wince every time the monthly bill comes in. It's about 50% of our total expenses, and we pay for more than a dozen other services. I wish it was priced on some combination of users + usage, rather than just users. We have an enormous mailing list, but only interact with a small portion of it 95% of the time.
That said, the segmentation and automation flows are nice.
That said, the segmentation and automation flows are nice.