I love the design studio and AI assistant, which makes it quite easy to navigate. The Customer.io academy is great, offering many emails with all the features, useful tips, links, and reminders. I love the possibility of deep and correct segmentation and the variety of tools to get in touch with the users. Customer.io gives us the possibility to combine different types like push, in-app, and email to be sent in one campaign. The AI assistant helps with correction and amendments and solves problems when I can't solve them myself. Despite the overwhelming setup, Customer.io is perfect for fast-growing needs, especially for onboarding and re-engaging users. Review collected by and hosted on G2.com.

There's a lot of information in the emails, which takes time to adjust to and study, but it's helpful that the team points out the next step. The setup is not easy and quite overwhelming, but we are growing fast and were looking for a tool like Customer.io. Review collected by and hosted on G2.com.

I use Customer.io for sending emails to engage and retain users. I find the data integration fairly easy, which simplifies my workflow. I like being able to create large email segmentations and campaigns, and the data monitoring and goal setting features are very helpful. The clean and simple UI makes implementation seem easy and helps me manage everything effectively. After running just one campaign, I got acclimated to the product, and I appreciate how the features align with my email campaign needs. The initial setup process was mostly smooth, and I like that I can track and verify if my emails are reaching the right segments, helping refine my strategies effectively. Review collected by and hosted on G2.com.

I think if the drafting phase of the email can be made easier. There should be more drag-and-drop features to design the emails, as most email writers and campaign designers are accustomed to using tools like Canva to make design emails. Customer.io can work on this single most aspect. Review collected by and hosted on G2.com.

The thing that keeps me on Customer.io is how much you can do inside a campaign without touching a developer. I build reactivation sequences where the copy changes based on whether a user ever visited the deposit page, what their balance looks like, and how many trades they've closed. All of that branching lives in one flow and stays readable.

Liquid templating is genuinely useful in production. The | default: filter alone has saved campaigns from breaking when an attribute is missing. I also track things like deposit count by incrementing it through event triggers and storing it back as a profile attribute, which lets me personalize messages across the full lifecycle without a data team involved.

The segment logic is precise enough to matter. Filtering on event attributes, not just event names, means I can target depositors who never traded separately from users who deposited and went quiet. Those are different people and they need different messages. Customer.io makes that distinction easy to build and easy to maintain.

On the integration side, we pipe behavioral events in real time and use them as triggers directly. The built-in request tester was useful during setup and saved a lot of back-and-forth. Sends are consistent, which matters when the content is time-sensitive.

Documentation covers most real-world edge cases. Liquid conditionals, webhook retries, attribute filtering nuances. I have rarely needed to open a ticket because the answer was usually already there.

The pricing model makes sense for how we actually operate. We are not paying for a static contact list where 60% of users have been inactive for months. Costs scale with real activity, which makes it straightforward to justify internally.

One thing worth mentioning: the built-in AI assistant has replaced a decent chunk of what I used to send to support. Not for complex setup questions, but for things like Liquid syntax, segment logic, figuring out why a trigger is not firing the way I expect. It usually gets me to an answer faster than waiting on a ticket, and the answers are specific enough to actually be useful rather than just pointing me to a doc I already read. Review collected by and hosted on G2.com.

The biggest friction point is around historical event data. Customer.io does not expose event counts through Liquid or JavaScript, so if you want to personalize based on how many times something has happened, like number of deposits or trades, you have to either engineer a workaround through event-triggered attribute increments or do a CSV backfill. For a platform that is otherwise quite flexible, that gap feels inconsistent.

Another recurring annoyance: we treat email as a sensitive attribute for compliance reasons, which is the right call, but a side effect is that individual user search by email gets disabled. Finding a specific test user for QA checks then becomes a longer process than it should be. When you are trying to quickly verify how a particular profile will render in a campaign, that extra friction adds up.

Segment preview and campaign analytics are functional but not deep. If you want to understand why a specific user did not enter a campaign or where exactly in a flow drop-off is happening, you end up doing more manual digging than you should need to. Better per-user journey visibility inside the campaign view would save a lot of time.

None of these are reasons to leave, but they are the kind of things that slow you down on a regular basis rather than being one-time setup issues. Review collected by and hosted on G2.com.

What I like best about Customer.io is how user-friendly the platform becomes once you start using it regularly. When I first joined, I expected it to be difficult to navigate, especially as a new user, but after spending time on the platform and learning the workflows, it became very seamless and easy to use. Setting up my first behavioural trigger campaign, sending a follow-up email when a user didn't complete onboarding, was simpler than I anticipated, and it worked exactly as expected.

I also appreciate the strong support and onboarding experience. Whenever I had questions, the support team responded quickly with helpful guidance. For instance, when I was unsure how to segment my audience based on user attributes, they walked me through it step by step. The onboarding process made it easier to understand how to set up workflows and use key features confidently, even as someone still relatively new to the platform. Review collected by and hosted on G2.com.

One limitation I've noticed with Customer.io is that once a campaign is archived, it cannot be edited. For example, I once needed to tweak the timing on a follow-up email sequence I had archived after a product launch, and I had to fully unarchive the entire campaign to make one small adjustment, then re-archive it afterwards. This adds unnecessary steps to what should be a quick fix. It can be frustrating when you want to reference or adjust parts of a past workflow without rebuilding from scratch, and a simple "edit while archived" option would make a meaningful difference in day-to-day efficiency. Review collected by and hosted on G2.com.

I think Customer.io is very user-friendly, and it's very easy to understand and navigate even for someone who has a more junior role like me. It's very easy to set up personalized campaigns, and I like that it's straightforward to design emails properly, depending on your needs. I also like that it's possible to use liquid codes to make some blocks of emails dynamic. Review collected by and hosted on G2.com.

I think, especially in terms of localization of content, the platform could be very buggy at times, and, also, it's happened very often that, despite me saving all the changes I made per language variation, the change was not saved, and that led to a lot of double work for me. Review collected by and hosted on G2.com.

I love Customer.io for its super flexible experience, and how it keeps the user interface easy enough to do things quickly. I appreciate that there's no shortage of tools and features, which help make the things we build more impactful. It's great that the team is consistently delivering new features that actually help my work instead of adding complexity. I really enjoy the click and drag builders that let us build and develop MVPs quickly while still having access to a wealth of data connectors. This makes our communications more personalized and reflective of user behavior. The way Customer.io connects to nearly our entire marketing stack, including our data ingestion systems, Twilio, and Meta, is fantastic. It's clear that the feature releases are consistently addressing platform issues to create a better experience. Review collected by and hosted on G2.com.

It can run a little slow when managing a lot of data. There seems to be a higher number of smaller outages, although the team is quick to report and address disruptions. It's also very difficult to respond to internal emergencies when I only have access to a mobile device. Review collected by and hosted on G2.com.

I like the fact that Customer.io is really simple to use, particularly as someone who is largely self-taught. The tool's simplicity made it easy to learn and easy to onboard new people into it. They are constantly adding new features and developing the platform, so there's always something new to try. These aspects help me save time on my work and make my tasks more efficient. Overall, it's really good to use. Review collected by and hosted on G2.com.

I don't have much to say about what I dislike - the support team is on-hand to help with any queries or technical problems, and as with most CRM tools it is as good as you make it. Review collected by and hosted on G2.com.

Overall, it is thorough and easy to operate campaigns and broadcast emails. Easy to integrate with tools like Segment, which helps our analytics Review collected by and hosted on G2.com.

There are a few oddities in the new Design Studio that are still annoying, for example, fighting with some of the drag and drop. That said, it has clearly been improving, so they seem self-aware Review collected by and hosted on G2.com.

I use Customer.io to send emails and in-app messages, and the Agent feature has been a massive help. It has really reduced my manual work, and I love that I can just ask it to look for something, and it takes care of it for me. The Agent acts like a personal assistant, a one-stop shop that I can describe tasks to and it handles them, plus it can pull data for me. Overall, it has made my life easier, and as I continue to train it, I'm confident it will continue to make my tasks even more manageable. The initial setup was relatively easy, and I'm using it integrated with Mobivate through webhook, with plans to integrate with Claude. I wouldn't trade Customer.io for any other product. Review collected by and hosted on G2.com.

The translation time. Whenever I translate, there are times it takes so much time. I wish it could be faster. Also, whenever I ask the agent to translate for me, it leaves weird characters or codes in replacement of emojis. I wish it just totally deletes the emoji instead of these codes. Review collected by and hosted on G2.com.

We use it for lifecycle marketing emails. What I love best is the depth of integrations, the ease with which we can use the different features. For instance, the segments and sequences are tough to figure in general but there are AI agents to help build those, so we love it. Review collected by and hosted on G2.com.

There are lots of UI changes very frequently so it gets a little tough to explain the new things each time I come on. Review collected by and hosted on G2.com.