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Research Report · April 2026 See it in action →
Research Report · April 2026

The Mobile‑First Messaging Playbook

What 124 marketing leaders from $10M+ ARR companies are doing to win customers on mobile — and why mobile-first is becoming the new default.

94.6%
of teams that shifted to mobile-first say it outperforms email-first approaches
91.9%
plan to pilot WhatsApp, RCS, or LINE within the next 12 months
91.8%
of teams live with WhatsApp, RCS, or LINE say performance has met or exceeded expectations
01
Takeaway One

Marketing teams are shifting to mobile‑first — and the data tells the story.

Today, only 30.6% of marketers still run email as their primary channel — meaning nearly 7 in 10 teams have already elevated mobile to primary or co-primary status. 22.6% say mobile is primary and email supplements, 38.7% say mobile and email are roughly equal, and another 7.3% are actively shifting. For the email-first holdouts, the direction of travel is unmistakable: 89.5% say they're either actively planning or exploring a shift to mobile-first in the next 12 months.

35.1%
Report a 25%+ lift in engagement or conversion after shifting to mobile-first
59.5%
See a 10–25% lift — zero respondents say mobile-first performed worse
89.5%
Of email-first holdouts are planning a shift to mobile-first within 12 months
Where mobile-first is winning — use cases by share of respondents
Promotional campaigns21.8%
Transactional alerts21.0%
Loyalty programs18.5%
Customer support16.2%
Onboarding flows14.1%
"

We ran a re-engagement flow using WhatsApp as the primary channel. It feels more personal than email or SMS, so people actually read it. Open rate: ~85–90%, conversion lift: ~8–10%.

Senior Director, Growth Marketing · SaaS
"

We ran an SMS + push re-engagement campaign with personalized offers and timed reminders. ~35% open rate, 12% conversion lift, and improved 30-day retention by ~8%.

Manager, Lifecycle / CRM Marketing · SaaS
Key Insight

The teams that have shifted are reporting real, measurable lift — and the teams that haven't shifted yet are the exception, not the rule. The question for 2026 isn't whether mobile deserves a larger role in the lifecycle — it's how quickly teams can shift investment, tooling, and strategy to match where their customers already are.

02
Takeaway Two

The mobile stack is broadening — and changing what mobile is for.

SMS still anchors mobile messaging for most teams — 86.3% actively use it — but it's no longer the only game in town. WhatsApp is now in active use at 72.6% of teams, second only to SMS. In-app messaging sits at 70.2%, push notifications at 55.6%...

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02
Takeaway Two

The mobile stack is broadening — and changing what mobile is for.

SMS still anchors mobile messaging for most teams — 86.3% actively use it — but it's no longer the only game in town. WhatsApp is now in active use at 72.6% of teams, second only to SMS. In-app messaging sits at 70.2%, push notifications at 55.6%, and emerging channels like RCS (16.9%) and LINE (12.9%) are quickly moving from "what's that?" to "we're piloting it." The pilot pipeline confirms the expansion: 91.9% of marketers say they're likely to pilot WhatsApp, RCS, or LINE in the next 12 months, including 50.8% who say they're very likely.

Mobile channels in active use (% of teams, multi-select, n=124)
SMS86.3%
WhatsApp72.6%
In-app messaging70.2%
Push notifications55.6%
RCS16.9%
LINE12.9%

But the more important shift is what these channels are being used for. When teams using WhatsApp, RCS, and LINE were asked about use cases, the #1 answer was customer support and two-way conversations (64.2%) — ahead of promotional campaigns (53.2%) and transactional notifications (46.8%). These newer channels are being used as something fundamentally different: a two-way, relationship-based surface.

What teams use WhatsApp, RCS & LINE for — top use cases (multi-select, n=109)
Customer support & two-way conversations64.2%
Promotional campaigns53.2%
Transactional notifications46.8%
Onboarding walkthroughs47.6%
Surveys & NPS36.3%

Five campaigns respondents called their most effective

Individual data points — one per respondent, spanning SaaS, Fintech, and Construction.

WhatsApp
95%
Open rate

Transactional WhatsApp automation for real-time status and delivery updates — moved order comms off email entirely.

Manager, Growth Marketing · Construction
Push + SMS
+20%
Activation lift

Onboarding flow with triggered tips and reminders over the first week. Better early retention — iterated on since.

Senior Director, General Marketing · Fintech
In-app
70%
Open rate · +20–25% conv.

Behavior-triggered in-app messages timed around user actions like drop-offs or inactivity.

Manager, Lifecycle / CRM · Fintech
SMS + Push
+12%
Conversion lift

Re-engagement campaign with personalized offers and timed reminders. ~35% open rate, ~8% lift in 30-day retention.

Manager, Lifecycle / CRM · SaaS
WhatsApp
85–90%
Open rate

"Feels more personal than email or SMS, so people actually read it." ~8–10% conversion lift on re-engagement flow.

Senior Director, Growth Marketing · SaaS

What marketers told us is coming next

Top five themes among 124 open-ended responses to: "What's the biggest change you expect to make to your mobile messaging strategy in the next 12 months?"

#1
AI & conversational messaging
"Moving from one-way broadcast SMS marketing to conversational AI-powered rich communication services."
20%
#2
WhatsApp expansion
"Massive investment in WhatsApp Flows — for everything from appointment booking to insurance claims and full e-commerce checkouts."
14%
#3
Real-time personalization & journeys
"Deepening personalization in in-app messaging by using more real-time behavioral data and predictive triggers."
7%
#4
Cross-channel orchestration
"Integrating AI-driven automation and centralized multi-channel dashboards for streamlined operations."
4%
#5
RCS adoption
"Shifting focus to RCS messaging, leveraging rich media and interactive content to boost engagement and conversions."
3%
Key Insight

The mobile stack is broadening, not consolidating — and the new channels are changing what mobile is for. WhatsApp is in active use at 72.6% of teams, and for teams live with WhatsApp, RCS, or LINE, 91.8% say performance has met or exceeded expectations — including 54.2% who say it exceeded them. In 2026, the question isn't "should we add another mobile channel?" — it's "which ones, and how do we orchestrate them together?"

03
Takeaway Three

Channel sprawl is outrunning orchestration maturity.

More channels, more data, and more customer expectations — but most teams are still stitching it together by hand. Only 1 in 3 marketers (35.5%) have a documented playbook or decision framework for deciding which message goes on which channel. Nearly half (46.8%) operate on general guidelines and gut feel. The personalization story looks similar: only 17.8% of teams have reached individualized, 1:1 personalization.

64.5%
Lack a documented cross-channel playbook or decision framework
82.2%
Haven't reached 1:1 personalization — using segment or event-triggered messaging instead
38.7%
Cite data quality as the #1 blocker to better personalization — ahead of budget or tooling
Personalization reality check — where teams are today (n=124)
Event-triggered behavioral messaging38.7%
Cohort-based segmentation30.6%
Individualized, 1:1 personalization17.8%
Basic merge tags only12.9%
The top frustrations mobile teams keep citing (open-ended, n=124)
Deliverability & reliability16%
Fragmentation across apps & channels8%
Integration & sync gaps8%
Cost & budget pressure5%
Message overload & relevance issues3%
"

My biggest frustration is how fragmented everything feels — conversations split across multiple apps. I end up missing messages or replying late because I forget to check one.

Senior Director, Growth Marketing · SaaS
"

Over the next 12 months, we're deepening personalization in in-app messaging with real-time behavioral data and predictive triggers — moving from one-off campaigns to automated, journey-based messaging.

Manager, Lifecycle / CRM Marketing · Fintech
Key Insight

Channel sprawl is outrunning orchestration maturity. 64.5% of marketers lack a documented cross-channel playbook. 82.2% haven't reached 1:1 personalization. And the #1 blocker isn't ambition or budget — it's data quality. The teams winning on mobile aren't the ones running the most channels. They're the ones with unified customer data, real-time behavioral triggers, and a single orchestration layer that can decide the right channel in the moment. That's the gap this report's data keeps pointing to — and it's the gap Customer.io is built to close.

Methodology

124
Completed responses
$10M+
Minimum company ARR
Mgr+
Minimum seniority
Apr '26
Fielding period

Original survey of marketing leaders actively managing mobile messaging programs at companies with $10M+ in annual revenue. Industries: SaaS, E-commerce, Fintech, Healthcare, Financial Services, Construction, Manufacturing, and Retail. Global: North America, EMEA, and APAC. All percentages are calculated from unique respondents per question. Multi-select questions (noted throughout) do not sum to 100%.

Built for the Mobile-First Era

The right message, on the right channel, for the right person, every time.

Customer.io unifies SMS, push, in-app, WhatsApp, and email in a single platform — with the real-time data, behavioral triggers, and cross-channel orchestration today's marketing teams need.

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© 2026 Customer.io · The Mobile-First Messaging Playbook · Research Report customer.io
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