Mobile-first sites that actually work on phones
US-based engineers rebuilding sites and web apps for real mobile performance — not just screens that shrink.
What this service delivers
Mobile traffic is now the majority of web traffic for most consumer and B2B sites. A site that is 'responsive' on paper but slow, cramped, or hard to tap on a real phone is a site that is quietly losing pipeline and revenue.
NextGen rebuilds sites and applications for true mobile-first performance — starting with how the site loads on a mid-range Android on a spotty connection, then working up. We fix the underlying architecture, not just the CSS.
Every engagement is measured against real device Core Web Vitals, tap-target audits, and conversion metrics on mobile specifically.
Why choose NextGen Coding
Most 'responsive' sites are desktop sites with breakpoints bolted on. They ship desktop-sized images, desktop-heavy JavaScript bundles, and desktop layouts that only technically resize on phones. That's why their mobile Core Web Vitals are red.
We approach mobile as the primary target: mobile-first CSS, per-device image formats, lazy hydration, and layouts that are designed for thumb reach and one-handed use.
Built for teams that need to move
Sites with poor mobile Core Web Vitals
LCP over 2.5s, CLS over 0.1, or INP over 200ms on mobile.
E-commerce with weak mobile conversion
Stores where mobile conversion lags desktop by more than 30%.
Content sites losing mobile SEO
Publishers seeing mobile rankings and traffic decline year over year.
Marketing sites hit by mobile-first indexing
B2B sites that dropped when Google shifted to mobile-first crawling.
Product surfaces used in the field
Web apps used by technicians, drivers, or field staff on phones and tablets.
Everything included in a NextGen build
Mobile performance audit
Real-device Core Web Vitals audit with prioritized fix list.
Image and asset optimization
Modern formats (AVIF/WebP), responsive srcset, and per-device delivery.
JavaScript budget
Per-route JS budget with code splitting and lazy hydration where it helps.
Mobile-first CSS
Tailwind or vanilla CSS refactor to mobile-first breakpoints and container queries.
Tap-target and gesture audit
Every interactive element sized and spaced for accurate thumb use.
Mobile-optimized navigation
Nav patterns designed for one-handed reach and glanceable hierarchy.
Form redesign for mobile
Autofill, correct keyboards, and single-column flows that don't require zoom.
Font loading strategy
Variable fonts, subsetting, and preload strategy to eliminate FOIT/FOUT.
Real device QA
Testing on iOS Safari, Android Chrome, and Samsung Internet on physical devices — not just emulators.
How the engagement runs
Audit
Real-device performance and UX audit with quantified opportunity.
Quick wins
High-leverage fixes shipped in the first two weeks — usually LCP and image weight.
Structural fixes
Layout refactor, JS budget enforcement, and hydration strategy.
Real device QA
QA across iOS, Android, and older devices in various network conditions.
Monitoring
Real-user monitoring so regressions are caught within hours, not months.
Transparent, US-market pricing
Mobile audit
Fixed-fee audit with prioritized fix list. Starting $3,500.
Performance sprint
2–4 week focused sprint on the highest-impact mobile issues. Starting $18,000.
Full mobile rebuild
Front-end refactor to mobile-first architecture. Scoped by codebase size.
All pricing is transparent and US-market calibrated. We don't compete on the lowest upfront number — we compete on delivering outcomes that generate the highest return on investment.
Results our clients experience
Mobile LCP down to 1.4s
A publisher client's mobile LCP dropped from 4.1s to 1.4s, recovering a 22% year-over-year mobile traffic loss.
Mobile conversion +38%
A DTC brand's mobile conversion rate rose 38% after a checkout redesign and JavaScript budget enforcement.
Field-tool adoption doubled
A logistics platform's field-tool weekly active use doubled after a mobile-first redesign of the driver interface.
Thought leadership & technical writing
Real device Core Web Vitals
Why lab metrics lie and how to measure what your users actually experience.
The JavaScript budget
How to set and enforce a per-route JS budget without losing features.
Mobile form patterns
The nine mobile form patterns responsible for most of the mobile conversion delta.
Objections, addressed
Our site is already responsive.+
Being technically responsive isn't the same as being mobile-optimized. If your mobile LCP is over 2.5s or your mobile conversion trails desktop by more than 30%, there's usually a large recoverable gap.
Can't we just make images smaller?+
That's a start, but not the whole story. Most mobile performance debt is in JavaScript, fonts, and layout thrash — not just image weight.
Isn't a native app better than mobile web?+
Sometimes. For high-engagement, offline-capable, or notification-driven experiences, a native app can win. For most content, marketing, and commerce, a fast mobile web experience outperforms because it's zero-friction to access.
Frequently asked questions
How do you measure mobile performance?+
Real-device Core Web Vitals via Chrome UX Report and real-user monitoring — not lab metrics from a fast connection.
Do you handle iOS Safari-specific bugs?+
Yes. iOS Safari has a distinctive set of quirks (position:fixed, viewport units, tap delay) that we handle explicitly on every engagement.
Can you improve mobile without a full rebuild?+
Often yes. Many wins come from image, font, and JS strategy without touching the underlying architecture.
How long until we see results?+
Usually within 4 weeks. Core Web Vitals improvements show in real-user metrics within 28 days of shipping fixes.
Engineering discipline. US-based delivery.
NextGen Coding Company builds websites and software as measurable business assets, not decorative art. Our team combines rigorous engineering discipline with design and conversion strategy, and every deliverable is accountable to an outcome. Clients partner with a single US-based team that owns strategy, design, build, and post-launch iteration.
All work is performed by US-based engineers and designers. Our team's proximity to US business hours, cultural context, and buyer expectations produces web experiences that resonate with domestic audiences — a nuance offshore teams frequently miss. We serve clients from New York and across the country, from early-stage startups through Fortune 500 enterprises.
Request a free consultation
Ready to discuss your project? Book a free 30-minute consultation with our NYC team. Response within one business day.
Explore related services
Start your project request
Tell us what you're building — engineering capacity, AI, QA, cloud, or a fixed-scope software engagement. Our NYC team responds within one business day.
- Response within 1 business day
- 30-minute discovery conversation
- Recommended engagement model & pricing
- NYC-focused — in-person available
Inbound sales only. All form information is encrypted in transit.