Quick answer
Most businesses should start with a fast, SEO-optimised website — it is how new customers find you on Google and AI search. Add a mobile app when customers return often (ordering, bookings, loyalty, tracking) and push notifications or device features add real value. Whatever you build, aim for Google’s Core Web Vitals: LCP ≤ 2.5s, INP ≤ 200ms and CLS ≤ 0.1.
Website vs mobile app: quick comparison
| Website | Mobile app | |
|---|---|---|
| Discoverability | High — Google, AI search, links | Lower — needs store search or marketing |
| Best for | Acquiring new customers | Retaining repeat customers |
| Engagement tools | Email, retargeting | Push notifications, home-screen presence |
| Device features | Limited | Camera, GPS, biometrics, offline |
| Upfront cost | Lower | Higher |
Signs your business needs a mobile app
- Customers order, book or check status every week.
- You run a loyalty programme or subscriptions.
- You need location, camera, offline access or real-time tracking.
- Push notifications would drive repeat sales.
Signs a website is enough (for now)
- Customers buy occasionally or need information before calling you.
- Your priority is being found on Google and generating leads.
- You are validating demand before investing in an app.
Speed matters: Core Web Vitals targets
Google’s Core Web Vitals measure real-user experience and are part of how pages are evaluated in search. “Good” thresholds, measured at the 75th percentile of visits, are:
| Metric | What it measures | Good |
|---|---|---|
| LCP — Largest Contentful Paint | Loading speed | ≤ 2.5 seconds |
| INP — Interaction to Next Paint | Responsiveness | ≤ 200 milliseconds |
| CLS — Cumulative Layout Shift | Visual stability | ≤ 0.1 |
The best of both: website + app working together
Many successful businesses use the website to attract and convert new customers, and the app to keep them coming back — sharing one backend, one admin panel and one customer database.
Frequently asked questions
Should a small business build a website or an app first?+
Usually a website first, because it brings in new customers through Google and AI search. Build an app once you have repeat customers who would use it often.
What are good Core Web Vitals scores?+
Largest Contentful Paint of 2.5 seconds or less, Interaction to Next Paint of 200 milliseconds or less, and Cumulative Layout Shift of 0.1 or less.
Sources
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