I like Customer.io because it's really simple and the automation system, along with the drag-and-drop feature, is really reliable. I use the automation system to quickly create or adjust any email marketing campaign or create any new campaign that I need for existing users. I also find the initial setup of Customer.io to be pretty easy. Review collected by and hosted on G2.com.

I find it lacks features like when I send a broadcast, it's kinda not clear how I do a follow-up. Review collected by and hosted on G2.com.

I like the simplicity of the Customer.io interface and how the tools and various improvements make my work easier. I am particularly pleased with the ability to change the trigger without having to recreate the campaign. I also find the snippet feature and the flexibility of segmentation very convenient. Compared to other platforms like esputnik and Sendpulse, Customer.io stands out. Review collected by and hosted on G2.com.

I would like Flow Control management to be more flexible in terms of working with attributes and segmentation for handling specific triggers. Review collected by and hosted on G2.com.

We work with a lot of data and within that data have a bunch of user segments. I would say one of Customerio's best features is their Dynamic data driven filtering. It makes working with large data sets seamless. Review collected by and hosted on G2.com.

I've been using the platform for roughly just over 2 years now and I can't find anything to fault that is worth discussing. I'm always learning new features as I go. Review collected by and hosted on G2.com.

I like how strongly Customer.io connects real-time user behavior to automated messaging without requiring heavy engineering work. The event-based automation and journey builder stand out because they let us build entire workflows based on exactly what users do in our product. This precision drastically improves engagement and product adoption by ensuring we send the right message at exactly the right moment. Customer.io automates personalized, real-time messaging across email, in-app notifications, and SMS. By triggering events directly based on user behavior, it significantly helps with user onboarding, retention, and product-led growth. Review collected by and hosted on G2.com.

The journey builder, while powerful, can become difficult to manage at scale. There's no easy way to duplicate, reuse, or modularize sections of flows. We end up rebuilding similar logic from scratch, which slows down our team. There's no good way to reuse or modularize parts of journeys. We can't save a section like a '3-touch re-engagement sequence' or a 'post-demo follow-up flow' as a reusable component. Every time we need that logic, we have to rebuild the entire branch from scratch — drag every trigger, wait step, condition, and message again. This is a massive waste of time. Review collected by and hosted on G2.com.

It's MCP integration that enables us to perform actions agentically. Review collected by and hosted on G2.com.

It's UI seems a little old school and can be tricky at times. Review collected by and hosted on G2.com.

It's UI is not overcomplicated; it's built in a way that makes it easy to pick up without much support from learning modules or customer service. What you see is what you get. Review collected by and hosted on G2.com.

I don't like that sending localized versions of your messages makes you unable to do A/B testing with one message and choose the one that outperforms the rest. Review collected by and hosted on G2.com.

I really like how Customer.io's behavior‑based automation and segmentation are both powerful and accessible, which is particularly valuable for our B2B SaaS team in Germany. It allows us to build very precise user journeys based on real product activity, not just static lists, and this level of personalization has significantly improved our onboarding completion and retention rates. The visual workflow builder stands out to me as it's intuitive enough for our marketing and customer success teams to create, edit, and launch complex automated sequences without needing help from engineers. Being able to trigger emails, in‑app messages, and delays based on users' actions in our product feels much more targeted than using generic email tools. I also found the initial setup quite straightforward, especially with existing user data and event tracking, and it didn't require much engineering time. Review collected by and hosted on G2.com.

I've noticed that template and dynamic content management could be better. Reusing blocks across multiple emails or journeys isn’t as smooth as it could be, and making global updates requires more manual work than it should. Right now, there’s no good way to create global, reusable content blocks like headers, footers, legal disclaimers, GDPR-compliant unsubscribe text, or button styles that update everywhere at once. If we need to change our company address, adjust a legal note, or update branding, we have to manually edit every single email template and every journey. That’s extremely time-consuming and prone to mistakes, which is risky for compliance in Germany. Review collected by and hosted on G2.com.

I like Customer.io's UI, design studio, and data importing/exporting features. The interface is intuitive, allowing me to build what I want without the need for a developer. I also appreciate the ability to launch and monitor email and push communication independently. The data personalization capability was a key reason for switching from SendGrid, as it lets me personalize communication based on data. Review collected by and hosted on G2.com.

I would like to be able to work with any data directly. Right now, sometimes I have to extract some event data in a segment in order to work with this data in a campaign. But it is fine, it is just a nice to have. Review collected by and hosted on G2.com.

The UX is very easy to navigate, and the support team is amazing. Also like the AI agent which is super handy for a few small tasks as of now Review collected by and hosted on G2.com.

Limitations on running AB tests, having universal control groups Review collected by and hosted on G2.com.

I use Customer.io as a Marketing Automation tool and find it super easy to use and very powerful. The journey builder is excellent and there is really almost nothing it can't do. As for integration, Customer.io turned out to be very flexible and easy to integrate, something our developers appreciated from the very first moment. Review collected by and hosted on G2.com.

It would be very good to be able to connect Customer.io with business metrics, such as CLV or Revenue, which are currently not available. In terms of analysis, the data is there, but the dashboards on the platform are limited. It is necessary to export them and work on them in Excel or some other platform (e.g. PowerBI) to make the most of them and obtain real insights. Review collected by and hosted on G2.com.