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 email-first is no longer the default.
Based on original research with marketing managers, directors, and VPs across SaaS, E-commerce, Fintech, and beyond.

The shift is already happening. 94.6% of teams that went mobile-first say it outperforms their email-first strategy, and 91.9% of marketers plan to pilot WhatsApp, RCS, or LINE in the next 12 months. But the teams winning aren't just adding channels — they're getting three harder things right: orchestrating across a fast-growing mobile stack, building compliance in from day one, and matching the right transactional-vs-promotional mix to every audience they serve.

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
90.9%
of B2B marketers say 75%+ of their mobile messaging is transactional
1

Mobile-First Isn't a Gamble — 94.6% of Teams Who Shifted Say It Outperforms Email

The "email-first" era is visibly ending. Only 30.6% of marketers still run email as their primary channel — and nine out of ten of them say they're actively planning or exploring a move to mobile-first. The teams that have already made the jump aren't second-guessing it.

Where marketers stand today: mobile vs. email
Share of respondents by current team approach (n=124)
Survey question: “Which statement best describes your team's approach?”
Mobile-first teams are seeing real lift
Performance vs. email-first, among teams that have shifted (n=37)
Survey question: “For teams that have gone mobile-first or shifted toward it: how has performance compared to email-first?”
Email-first teams are getting off the fence
Likelihood of shifting to a mobile-first approach in the next 12 months, among teams currently running email-first (n=38)
Survey question: “How likely is your team to shift to a mobile-first approach in the next 12 months?”
Where mobile-first is actually winning
Use cases where marketers report mobile-first outperforms email · multi-select, respondents can select more than one (n=124)
Survey question (multi-select): “In which use cases does mobile-first outperform email-first? (Select all that apply)”

Key Insight

Mobile-first isn't a bet — it's a performance story. Among teams that have already shifted, 35.1% report a 25%+ lift in engagement or conversion, and another 59.5% see a 10–25% lift. And the lift isn't concentrated in one place: promotional campaigns, transactional alerts, and loyalty programs are all being won on mobile. Combined with 89.5% of email-first teams planning to move, the 2026 default for customer engagement is mobile.

"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
2

Beyond SMS: 9 in 10 Marketers Will Pilot WhatsApp, RCS, or LINE in 12 Months

SMS still anchors mobile messaging for most teams — but it's no longer the only game in town. WhatsApp is now the second most-used channel, RCS is emerging fast, and in-app messaging is already in active use at 70.2% of teams.

Mobile channels in active use
% of marketers currently using each channel · multi-select, respondents can select more than one (n=124)
Survey question (multi-select): “Which mobile messaging channels does your team currently use? (Select all that apply)”
Which channel drives the most impact?
Single channel selected as top performer (n=124)
Survey question: “Which mobile channel drives the most impact for your business today?”
WhatsApp, RCS & LINE: the 12-month pilot pipeline
Likelihood of piloting one of these channels in the next 12 months (n=124)
Survey question: “How likely are you to pilot one of these in the next 12 months?”
Early adopters of WhatsApp, RCS & LINE are getting results
Performance vs. expectations, among marketers who've launched these channels (n=109)
Survey question: “How has performance compared to your expectations?”
What teams are actually using WhatsApp, RCS & LINE for
Top use cases for these channels · multi-select, respondents can select more than one (n=109 using or exploring these channels)
Survey question (multi-select): “What are you using WhatsApp, RCS, or LINE for? (Select all that apply)”
In-app & rich push: from broadcast to relationship
In-app and richer push experiences marketers have in production today — increasingly used as two-way, relationship-building surfaces, not one-way broadcast. Multi-select, respondents can select more than one (n=124)
Survey question (multi-select): “Which in-app and rich push experiences do you have in production? (Select all that apply)”
PLAYBOOK IN PRACTICE

Five campaigns respondents called their most effective

Each card is one respondent's self-reported campaign from the past year — individual data points, not synthesized averages. Together the five span SaaS, Fintech, and Construction, and mix single-channel, multi-channel, promotional, and transactional plays.

WhatsApp
85–90%
Open rate
Re-engagement flow using WhatsApp as the primary channel. "Feels more personal than email or SMS, so people actually read it." ~8–10% conversion lift.
Senior Director, Growth Marketing · SaaS
Push + SMS
+20%
Activation lift
Onboarding flow for new users with triggered tips and reminders over the first week. Drove a ~20% lift in activation plus better early retention — iterated on since.
Senior Director, General Marketing · Fintech
In-app
70%
Open rate · +20–25% conv
Behavior-triggered in-app messages for onboarding and re-engagement — timed around user actions like drop-offs or inactivity. Noticeable early-retention improvement.
Manager, Lifecycle / CRM Marketing · Fintech
SMS + Push
+12%
Conversion lift
Re-engagement campaign with personalized offers and timed reminders across SMS and push. ~35% open rate and a ~8% lift in 30-day retention.
Manager, Lifecycle / CRM Marketing · SaaS
WhatsApp
95%
Open rate
Transactional WhatsApp automation for real-time status and delivery updates — moved order communications off email entirely. Significantly improved team coordination too.
Manager, Growth Marketing · Construction
WHERE MARKETERS ARE HEADING

The five shifts marketers told us are coming next

We asked all 124 respondents: "What's the biggest change you expect to make to your mobile messaging strategy in the next 12 months?" These are the five most-cited themes in their answers. The remaining responses described smaller themes or company-specific plans — so the shares below don't sum to 100%.

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

Key Insight

The mobile stack is broadening, not consolidating. WhatsApp is now in active use by 72.6% of marketers — second only to SMS — and of those who've gone live with WhatsApp, RCS, or LINE, 91.8% say performance has met or exceeded expectations. And the way in-app and rich push are being used — 47.6% for onboarding walkthroughs, 36.3% for surveys and NPS, 33.1% for images and media in push — shows the shift from one-way broadcast to two-way relationship-building. For marketing teams, the question in 2026 is no longer "should we add another mobile channel?" but "which ones, and how do we orchestrate them together?"

"We expect to deploy action-oriented agents. WhatsApp as core infrastructure — massive investment in WhatsApp Flows for everything from appointment booking to insurance claims and full e-commerce checkouts."
— Senior Director, General Marketing · SaaS
"The biggest shift in mobile messaging strategy is the transition from one-way broadcast SMS to AI-powered, rich conversational messaging, driven primarily by the maturation of RCS and two-way conversational AI."
— Manager, General Marketing · Construction
3

1 in 3 Teams Have a Playbook. The Rest Are Improvising.

More channels, more data, and more expectation from customers — but most teams are still stitching it together by hand. Only 1 in 3 marketers have a documented cross-channel playbook. Only 17.8% have reached 1:1 personalization. And the #1 challenge holding everyone back is the same: the data isn't good enough, and the channels don't talk to each other.

How teams decide which message goes on which channel
Multi-channel orchestration approach (n=124)
Survey question: “When running a multi-channel campaign (for example, email + SMS + push), how do you decide which message goes on which channel?”
Personalization reality check
Level of personalization marketers are achieving on mobile today (n=124)
Survey question: “What level of personalization are you achieving on mobile today?”
What's actually getting in the way
Biggest mobile messaging challenges · multi-select, respondents can select more than one (n=124)
Survey question (multi-select): “What are your biggest mobile messaging challenges? (Select all that apply)”
The messiest part of orchestrating across channels
Single biggest pain point cited by marketers running multi-channel campaigns (n=124)
Survey question: “What's the messiest part of orchestrating across channels?”
What's blocking better personalization
Biggest barrier to mobile personalization (n=124)
Survey question: “What's the biggest barrier to better personalization on mobile?”
Attribution: half-confident, half in the dark
How clearly marketers can see what's driving mobile results (n=124)
Survey question: “Do you feel like you have a clear picture of what's actually driving results, or is attribution still a bit of a black box?”
VOICE OF THE MARKETER

The five frustrations mobile teams keep coming back to

We asked all 124 respondents: "What is your biggest frustration with your current mobile messaging setup?" These are the five most-cited patterns — each one a direct symptom of the orchestration gap. The remaining responses were unique to specific setups or too brief to cluster, so the shares below don't sum to 100%.

#1 MOST-CITED
Deliverability & reliability
16% of respondents
"The biggest frustration is the verification and integration required to ensure those messages actually arrive and provide a good experience."
#2 (TIED)
Fragmentation across apps & channels
8% of respondents
"Managing multiple platforms is tiring; I dislike fragmented conversations and the lack of unified cross-app messaging."
#2 (TIED)
Integration & sync gaps
8% of respondents
"My biggest frustration is message overload and lack of seamless integration across platforms."
#4
Cost & budget pressure
5% of respondents
"The cost is a bit of a frustration — especially as we try to expand across more channels."
#5
Message overload & relevance
3% of respondents
"The biggest frustration is when messages are sent out in an irrelevant fashion."

Key Insight

Channel sprawl is outrunning orchestration maturity. 64.5% of marketers lack a documented cross-channel playbook, and 82.2% haven't reached individualized, 1:1 personalization. The #1 blocker isn't tools — it's data quality (cited by 38.7% as the top personalization barrier). And while 51.6% say they're "very confident" in attribution, nearly as many (47.6%) admit they can see trends but not the full picture. The teams winning on mobile aren't the ones running the most channels — they're the ones with unified customer data, real-time triggers, and a single orchestration layer that can decide the right channel in the moment.

"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
4

1 in 3 Marketers Want Compliance Baked Into Their Messaging Platform

Compliance used to be something marketers worked around. In 2026, it's increasingly something they buy for. For nearly 3 in 10 marketers, compliance is either the primary constraint on their strategy or actively limiting their programs today — and when asked what would help most, the top answer isn't more regulatory guidance. It's built-in compliance features in the messaging platform itself.

Compliance: background noise or active constraint?
Impact of opt-in, HIPAA, GDPR, and regional regulations on strategy (n=124)
Survey question: “How much does compliance (like opt-in management, HIPAA, GDPR, or regional regulations) shape your mobile messaging decisions?”
What marketers actually want from compliance tools
Most wanted support for navigating mobile compliance (n=124)
Survey question: “What would be most helpful to help you navigate compliance with mobile messaging?”

Key Insight

29.8% of marketers say compliance is either the primary constraint on their mobile strategy or actively limiting what they can do. And when asked what would help most, the #1 answer — from 31.5% of respondents — is built-in compliance features inside the messaging platform itself. Marketers don't want more regulatory PDFs; they want the guardrails baked into the tool. For teams operating in regulated industries, the compliance capabilities of the messaging platform have quietly become a buying criterion.

"Integration issues and compliance are the primary constraint on our strategy — we have some stove-pipe issues to resolve still."
— Senior Director, Lifecycle / CRM Marketing · SaaS
"The biggest frustration is the verification and integration required to make sure those messages actually arrive and provide a good experience."
— Senior Director, General Marketing · SaaS
5

91% of B2B Messaging is Transactional — But Only 43% of B2C

Here's where most mobile strategies quietly break down: teams treat mobile as one channel when it's really three different jobs at once. B2B marketers use it as a transactional utility. B2C teams use it as a marketing megaphone. Hybrid businesses need both — and most businesses are hybrid. Getting the transactional-vs-promotional mix right for each audience isn't a nice-to-have; it's where mobile strategies win or lose.

B2C, B2B, or both?
Primary customer type (n=124)
Survey question: “Are your company's customers primarily other businesses, consumers, or both?”
Transactional vs. promotional — the overall split
% of mobile messaging that is transactional vs. promotional (n=124)
Survey question: “Approximately what percentage of your mobile messaging is transactional vs. promotional?”
B2B leans transactional. B2C leans promotional. Hybrids sit in the middle.
Share of each audience type reporting 75%+ transactional mix vs. 75%+ promotional mix
Derived: Cross-tabulation of two survey questions: customer type and transactional-vs-promotional mix (see preceding charts for verbatim wording)
The mix is moving — and mostly toward transactional
How marketers' transactional-vs-promotional balance has changed in the past 12 months (n=113, excludes those who skipped or didn't know)
Survey question: “Has your balance of transactional vs. promotional messaging changed in the past 12 months?”

Key Insight

The teams winning on mobile aren't forcing one playbook onto different audiences. They're running distinct lifecycle logic for B2B accounts, B2C consumers, and hybrid segments — on a single platform, with one view of every customer. That's the real mobile-first capability gap: not sending more messages, but sending the right mix, to the right audience, on the right channel, at the right moment. That's the work.

"Our most effective WhatsApp flow is order status and delivery confirmations. We target clients with pending or in-progress orders with automated updates and personalized follow-ups."
— Manager, General Marketing · Manufacturing
"Most effective via SMS: we sent a limited-time promotion to subscribers offering 20% off. Open rate ~98%, 15% conversion rate — a 5% lift in overall sales."
— Senior Director, Customer Marketing · Fintech

Built for the Mobile-First Era

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 to move beyond email-first. With HIPAA-eligible infrastructure and built-in compliance controls, Customer.io is trusted by regulated industries and consumer brands alike. Whether you're piloting RCS, scaling WhatsApp, or rebuilding your lifecycle program around mobile, Customer.io is where the mobile-first playbook comes to life.

See Customer.io in Action →

Methodology

This report is based on an original survey of marketing leaders actively managing mobile messaging programs at companies with $10M+ in annual revenue, fielded in April 2026.

124
Completed responses
Manager+
Minimum seniority required
$10M+
Minimum company ARR
Apr 2026
Fielding period

Respondents by marketing function

Survey question: “Which best describes your current role and level? (Single select)”

Respondents by industry

Survey question: “What best describes your company?”

Respondents by region

Survey question: “Where are you based?”
A note on percentages: All percentages in this report are calculated from unique respondents, not total mentions. Single-select questions sum to 100%. Multi-select questions (clearly labeled) do not sum to 100% because respondents could choose more than one option. Where a chart's base (n) differs from the full sample of 124, it is noted on the chart — typically because a question was only shown to a relevant subset (e.g., performance vs. email-first was only asked of teams that had gone mobile-first).
© 2026 Customer.io · The Mobile-First Messaging Playbook · Research Report
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