World Spa
Brooklyn's 50,000 sq ft wellness destination. WordPress site, the iOS app (Android on the way), an AI concierge, booking and payments through Adyen, and ongoing SEO and AI-search work.
Open worldspa.comAI systems we've built, and still run.
Simple4u builds AI systems for small and mid-size businesses: marketing analytics, booking and payments, customer service, and the software around them. Below are the clients we can name and the shapes of work we can only describe.
Live, one click each
Open the work itself. No video, no deck.
Sites and products we built and still run. Every link is the live thing, the way a guest or a search assistant sees it.
worldspa.com
Site, booking and payments, the iOS app (Android on the way), SEO and AI-search presence. Client since 2023.
simple4u.io/booking-funnel#chat
Our AI front desk, built the same way as World Spa's, which answers about 40 guest questions a day. Ask it about us.
The World Spa app
On the App Store: guests browse treatments and book from their phone. We built it and keep it running.
nycbyyacht.com
Yacht charter, New York: site, booking flow, SEO and marketing analytics.
simple4u.ai
The AI Office: a sales office that finds your buyers, with a marketing analyst, a content writer, a project manager and client service. Free scan of your site to start.
guard.simple4uhq.com
Revenue Guard: the marketing analytics console. Every number labeled measured, computed or excluded.
github.com/Simple4uhq
Open source: the memory layer, the agent platform, the SHAITS standard. Read the code before the call.
abcpreschoolny.com
Preschool, Woodside, Queens: site and enrollment flow.
paradiseflowershop.com
Flower shop, Manalapan, NJ: site and online ordering.
Anchor case study
Our longest-running client, three years and counting.
World Spa has been a client since 2023. What started as a website grew into a full set of AI systems: booking, payments, an AI concierge, and marketing analytics, running alongside the spa's own marketer.
Client since 2023 · Premium spa group, Brooklyn
World Spa: apps, AI concierge, booking and payments, SEO and GEO
We built the WordPress site, the iOS app with Android on the way, an AI concierge answering about 40 guest questions a day, a booking and payments integration with Adyen, and ongoing SEO and AI-search (GEO) work. The site gets about 130,000 visits a month from all channels; more than 1,000 Google clicks a month come from people who searched for a spa, not for World Spa ("spa brooklyn", "hammam nyc"). We work alongside the spa's own in-house marketer.
Read full case studySelected named work
Clients we can name.
Live previews of the systems we've built. Click any preview to expand it in place, or open the full site in a new tab.
NYC By Yacht
Brooklyn yacht charter. A full rebuild of the site since December 2025, booking through their own LatePoint and Square, server-side purchase tracking, a rebuilt Google Business Profile, and local SEO. Ranked #1–3 in Google Maps within about 2 km of the marina.
Open nycbyyacht.comABC Preschool NY
Preschool in Woodside, Queens: warm, parent-friendly, functional. Online enrollment flow, location info, virtual tour gallery.
Open abcpreschoolny.comParadise Flower Shop
Florist in Manalapan, New Jersey. Built from scratch: same-day delivery booking, occasion-based bouquet catalog, online checkout, custom order intake.
Open paradiseflowershop.comOr book the call
Fifteen minutes, no deck. If we are not the right team, you will hear that on the call and get a name of who is.
Prefer to talk first: book a call with Slava
Phone: (929) 640-6940
Email: office@simple4u.io
Based in Brooklyn, NY. We work with clients anywhere; in New York we come to you.
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