Customer IO

Automate powerful behavioral messages for web & mobile apps

★★★★★ 4.6/5
FactScore™ 64.7
VS

Folderly

Make the inbox your only destination folder

★★★★★ 5.0/5
FactScore™ 84.5

Updated February 2026

Customer IO Folderly
Rating 4.6★ 5.0★
Reviews 24 48
Pros 10 17
FactScore™ 64.7 84.5

FactScore™ Comparison

FactScore™ weighs both quality (rating) and popularity (reviews) for a fairer ranking than stars alone.

64.7
Customer IO FactScore™
👑
84.5
Folderly FactScore™
★ Folderly wins on FactScore™

Pros & Cons

Only in Customer IO — Pros

Behavioral messaging Personalized communication Automation capabilities Free startup plan Segmentation User engagement Email builder Multi-channel messaging Workflow customization

Both tools — Pros

Customer support

Only in Folderly — Pros

Email deliverability User-friendly interface Spam prevention Comprehensive solution Robust features Email outreach optimization Email spam words checker DNS settings management Increased open rates AI-driven approach Best practices recommendations Blacklist monitoring Spam trigger detection Email infrastructure analysis Real-time monitoring Simple setup

Only in Customer IO — Cons

Complex interface Email editor issues Inflexible journeys Limited CMS features Slow UI

Both tools — Cons

Only in Folderly — Cons

Details

Customer IO Folderly
Categories Email marketing, Marketing automation platforms, Customer loyalty platforms Email marketing, Marketing automation platforms, Safety and Privacy platforms, AI Infrastructure Tools
Platforms Web Web
Became Popular January 29, 2014 November 26, 2020
Website customer.io folderly.com

Who Should Pick Which?

Choose Customer IO if...

  • Behavioral messaging
  • Personalized communication
  • Automation capabilities

Choose Folderly if...

  • Email deliverability
  • User-friendly interface
  • Spam prevention

With a FactScore™ of 64.7 vs 84.5, Folderly leads in community reception. Customer IO uniquely offers Behavioral messaging and Personalized communication, while Folderly stands out for Email deliverability and User-friendly interface.

3

What Users Say

Customer IO

V
Vova Jan 14, 2025
★★★★★

We made the switch to Customer.io after trying out Loops and Userlist, and it’s been a great decision. It’s powerful enough to handle all our SaaS communication needs, yet still easy to use. It wor...

D
Danielle May 13, 2025
★★★★★

Our new email campaign provider with a user-friendly interface, clear visual logic for campaign triggers, and lots of customization. The level of flexibility has encouraged us to be more creative a...

A
Ali Dec 29, 2024
★★★★★

Customer IO stands out for its powerful automation capabilities and behavioral messaging tools. It allows us to create highly personalized communication workflows, improving engagement and retentio...

Folderly

S
Sofiia Nov 20, 2023
★★★★★

I think Folderly is truly changing the game in the email deliverability industry, leaving warmup solutions in the dust 😍 It's more than diagnosing and applying a "patch." This solution fixes deliv...

D
Dariia Nov 6, 2023
★★★★★

I've been here since the early days of Folderly, witnessing its growth and development. With our ever-evolving platform, we're now proud to have helped hundreds of clients! Our Customer Success tea...

M
Michael Nov 7, 2023
★★★★★

Proper email deliverability prepares and maintains the entire email infrastructure. Google Startups Fund backs Folderly to create a comprehensive deliverability solution. This includes managing dom...

Frequently Asked Questions

Which is better, Customer IO or Folderly?

Based on FactScore™, Folderly leads with a score of 84.5 vs 64.7. Folderly has a higher rating of 5.0★ compared to 4.6★.

What are the pros of Customer IO compared to Folderly?

Customer IO uniquely offers: Behavioral messaging, Personalized communication, Automation capabilities, Free startup plan, Segmentation.

What are the pros of Folderly compared to Customer IO?

Folderly uniquely offers: Email deliverability, User-friendly interface, Spam prevention, Comprehensive solution, Robust features.

Is Customer IO better rated than Folderly?

Customer IO is rated 4.6★ from 24 reviews. Folderly is rated 5.0★ from 48 reviews.

What is the FactScore™ of Customer IO and Folderly?

FactScore™ weighs rating and review volume together. Customer IO scores 64.7 and Folderly scores 84.5.

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