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Comparison · Mkt Auto

Customer.io vs Sulu

A side-by-side editorial comparison of Customer.io and Sulu — release velocity, themes, recent moves, and the top alternatives to consider.

Customer.io vs Sulu: at a glance

FeatureCustomer.ioSulu
SectorMkt AutoMkt Auto
Velocity score7.55.0
Sparks · 30d20
Top themeslocation-triggers, live-notifications, device-surfaces, byo-sms-providerssymfony-cms, dual-branch-releases, ckeditor, doctrine-migrations
Last editorial update1d ago1h ago
WebsiteVisit →Visit →

What is Customer.io?

Customer.io's summer wave pushes messaging into location triggers and live device surfaces.

Customer.io shipped a dense summer release: geofence-based triggers, live notifications that render as iOS Live Activities and Android 16 Live Updates, an in-app notification inbox, and support for bringing your own SMS provider via Sinch, Infobip, or Vonage. Alongside the headline channels are workflow-level fixes that matter operationally — channel-based message frequency limits, date triggers on custom objects, and multiple mobile apps per workspace. LLM actions gained reusable knowledge sources so prompts can reference a file or Drive doc instead of repeating pasted text.

Read the full Customer.io trajectory →

What is Sulu?

Sulu ships 2.6 and 3.0 in lockstep, and the 3.0 line still reads like a maintenance branch.

Sulu is a Symfony-based CMS for developer-built sites, and its release process is a synchronised pair: every 3.0.x patch ships within a minute of the matching 2.6.x patch, carrying largely the same pull requests. Six releases in five months — 3.0.8/2.6.25, 3.0.7/2.6.24, 3.0.6/2.6.23 — are almost entirely fixes, editor upgrades and framework compatibility work. A security advisory was patched across both branches in March.

Read the full Sulu trajectory →

Customer.io vs Sulu: editorial side-by-side

Customer.io logo
Customer.io
MKT AUTO
7.5

Customer.io's summer wave pushes messaging into location triggers and live device surfaces.

◆ Current state

Customer.io shipped a dense summer release: geofence-based triggers, live notifications that render as iOS Live Activities and Android 16 Live Updates, an in-app notification inbox, and support for bringing your own SMS provider via Sinch, Infobip, or Vonage. Alongside the headline channels are workflow-level fixes that matter operationally — channel-based message frequency limits, date triggers on custom objects, and multiple mobile apps per workspace. LLM actions gained reusable knowledge sources so prompts can reference a file or Drive doc instead of repeating pasted text.

◆ Where it's heading

The direction is toward owning more of the device surface rather than more of the inbox. Live Activities, the notification inbox, and geofences all move triggering and rendering closer to where the customer physically is, which is a different competitive axis than email deliverability. At the same time, BYO SMS providers and channel-level frequency caps loosen delivery lock-in and hand rate control to the operator — a platform posture, not a messaging-tool one.

◆ Prediction

Expect the remaining device-native surfaces to fill in — richer inbox and Live Activity templating — and expect LLM actions to keep absorbing workflow context now that knowledge sources are reusable.

S
Sulu
MKT AUTO
5.0

Sulu ships 2.6 and 3.0 in lockstep, and the 3.0 line still reads like a maintenance branch.

◆ Current state

Sulu is a Symfony-based CMS for developer-built sites, and its release process is a synchronised pair: every 3.0.x patch ships within a minute of the matching 2.6.x patch, carrying largely the same pull requests. Six releases in five months — 3.0.8/2.6.25, 3.0.7/2.6.24, 3.0.6/2.6.23 — are almost entirely fixes, editor upgrades and framework compatibility work. A security advisory was patched across both branches in March.

◆ Where it's heading

Three threads run through the pairs. Editor upkeep is constant, with CKEditor moving to 47 LTS and then 48 and the fallout — table widgets, webpack font builds — fixed release by release. Framework compatibility is the second: Request->get calls replaced for Symfony 8, PHPUnit 13 and PHPStan kept green on lowest dependencies. The third and most interesting is data-model cleanup on the 3.0 side, where tags migrated from names to IDs behind a newly added DoctrineMigrationsBundle, with smart-content filters reworked to match. What is not visible is any capability that exists on 3.0 and not on 2.6 — a major version that is not yet behaving like one.

◆ Prediction

Expect the paired-release rhythm to continue with more Symfony 8 preparation and CKEditor 48 fallout. The open question is when 3.0 starts receiving work that is not upmerged from 2.6; until then the major version number is not buying users anything.

Alternatives to Customer.io and Sulu

Other Mkt Auto products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Customer.io or Sulu.

See all Customer.io alternatives → · See all Sulu alternatives →

Recent activity from Customer.io and Sulu

Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.

  1. 2d agoCustomer.ioAdd reusable knowledge sources to LLM actions
  2. 2d agoCustomer.ioSummer release: geofences, live notifications, more SMS providers
  3. 2d agoCustomer.ioGeofences: message people when they enter or exit a location
  4. 2d agoCustomer.ioSet up SMS with Sinch, Infobip, or Vonage
  5. 3d agoCustomer.ioSend push notifications to multiple mobile apps in one workspace
  6. 8d agoCustomer.ioLive notifications: real-time updates without opening your app
  7. 15d agoSuluSulu 3.0.8 validates selection filter params at build time
  8. 15d agoSuluSulu 2.6.25 adds a redirect after SSO login
  9. 2mo agoSuluSulu 3.0.7 fixes smart-content filtering and speeds up indexing
  10. 2mo agoSuluSulu 2.6.24 upgrades CKEditor to version 48
  11. 2mo agoSuluSulu 3.0.6 migrates tag names to IDs with Doctrine migrations
  12. 2mo agoSuluSulu 2.6.23 moves to CKEditor 47 LTS and preps Symfony 8

Frequently asked questions

What is the difference between Customer.io and Sulu?

They serve adjacent needs but don't currently overlap on shipped themes. Customer.io is currently shipping more aggressively (velocity 7.5 vs 5.0), with 2 editorial sparks in the last 30 days against 0. See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.

Is Customer.io better than Sulu?

Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Customer.io is currently shipping more aggressively (velocity 7.5 vs 5.0), with 2 editorial sparks in the last 30 days against 0. For your specific use case, the alternatives sections above list other Mkt Auto products to evaluate alongside.

What are the best alternatives to Customer.io?

Top Customer.io alternatives in Mkt Auto are ranked by recent ship velocity. Browse the "Customer.io alternatives" section above for the current picks, or visit /alternatives/customerio for the full list with editorial commentary on each.

What are the best alternatives to Sulu?

Top Sulu alternatives in Mkt Auto are ranked by recent ship velocity. Browse the "Sulu alternatives" section above for the current picks, or visit /alternatives/sulu for the full list with editorial commentary on each.