- About ZentroStack
About ZentroStack: Built to Stop Small Businesses Losing Customers
About ZentroStack in one line: it answers calls and messages, keeps every lead in one place and helps you get paid, so a small team can run like a bigger one.
Our Story
Subodh Banerjee and Rajeeb Mookhopadhyay started ZentroStack to give small businesses one simple system to run on, instead of a pile of disconnected tools. Subodh has 30+ years in engineering, enterprise sales and business operations in Silicon Valley. Rajeeb is a software developer and digital marketer with 20+ years of experience across the UAE, Qatar and India. He builds the product and knows how businesses get found and win customers.
The Problem We Kept Seeing
We are Subodh Banerjee and Rajeeb Mookhopadhyay. Between us we have more than 50 years in engineering, enterprise sales and digital marketing, in Silicon Valley, the UAE, Qatar and India, much of it spent helping businesses get more leads.
The same thing happened again and again. The marketing worked and the enquiries came in, but many were lost before anyone replied.
The tools that could fix this were built for bigger companies, or sold as separate apps that didn’t talk to each other. So we built one platform that does the whole job.
A missed call
The owner was on a job when it rang.
A late reply
The WhatsApp message got answered the next day.
A forgotten quote
It went out, and nobody followed it up.
The People Behind ZentroStack
Subodh Banerjee: Founder & Owner, ZentroStack
Subodh Banerjee is the founder and owner of ZentroStack, which operates under Zentro Technologies in San Jose, California. He has more than 30 years of experience across engineering, enterprise sales and business operations.
He started as an applications engineer at Intel and AMD. He then moved into sales engineering at Pericom Semiconductor and Hyundai Electronics. Later he was International Director of Sales at SiGe Semiconductor and Wintec Industries, where he negotiated multi-million-dollar contracts across Europe and Southeast Asia. Since 2016 he has been a licensed California Real Estate Broker, managing commercial and residential property portfolios.
He has an engineering background, years of running sales pipelines on CRMs, and hands-on experience running a business. That is why ZentroStack focuses on practical tools that small businesses can actually use day to day.
He holds a B.S. in Electrical Engineering from Imperial College London and an M.S. in Computer Technology from San Jose State University.
- B.S. Electrical Engineering, Imperial College London
- M.S. Computer Technology, San Jose State University
- Intel, AMD, Pericom, Hyundai Electronics, SiGe, Wintec
- San Jose, California
Rajeeb Mookhopadhyay: Founder & CEO, ZentroStack
Rajeeb Mookhopadhyay is the founder and CEO of ZentroStack, and he builds the product. Based in Dubai, UAE, he has worked in sales and digital growth since 2004, helping businesses across the UAE, Qatar and India get more leads.
He started his career as a programmer, writing COBOL, C, C++, Java and JavaScript, before moving into marketing. That mix shapes ZentroStack: every feature has to work technically and has to bring in or keep a customer. As a digital marketing lead he cut cost per acquisition by 45%, raised qualified lead volume by 65% and reached a 3.5x return on ad spend.
He also runs rajeebm.pro, where he builds websites, automation and lead systems for small business owners, and WebsiteIn72, which builds business websites in 72 hours. zentroMSG answers live enquiries for WebsiteIn72 every day, so he uses the product in his own business.
He holds a B.Com (Honours) and an MBA in Marketing, and is Google certified in Fundamentals of Digital Marketing and Google Ads Display.
- B.Com (Honours) and MBA in Marketing
- Google certified: Digital Marketing, Google Ads Display
- Programmer first: COBOL, C, C++, Java, JavaScript
- Dubai, UAE
How We Build ZentroStack
Answer every customer
A missed enquiry is lost revenue. The product exists to stop that.
Honest AI
Our AI never pretends to be a person, never invents prices or promises, and hands over to you when it should.
Simple beats clever
Small business owners don't have time for weeks of setup.
Pay for what you use
Start with one app and add more only when you need them.
Built for Service Businesses Worldwide
Trades, cleaning companies, clinics, salons, law firms and other service businesses that win work by phone, WhatsApp and social messages, in any market.
Most of them have the same story: a small team, a busy phone and customers who want an answer now. ZentroStack gives that team an AI that answers first, one place for every lead and a simple way to quote, book and get paid. You can start with a single app, such as call answering or WhatsApp, and add the rest when it makes sense for your business.
About ZentroStack: Five Apps, One Login
zentroVoice
An AI answering service that picks up your calls 24/7 and saves every lead.
zentroMSG
A WhatsApp chatbot for business that also answers Instagram and Messenger.
zentroCRM
A CRM for small business where every call and chat becomes a lead.
zentroBook
An online booking system with its own calendar.
Quotes and invoicing
Quote and invoice software with e-signature, instalments and reminders.
One customer record
Every app shares the same data, so nothing is copied between tools.
Why ZentroStack Is One Platform, Not Five Apps
Small businesses already pay for too many tools. Each one has its own login, its own bill and its own copy of the customer list, and none of them talk to each other. When a lead calls, then messages on WhatsApp, then books, the story is split across three apps.
That is why everything you read about ZentroStack comes back to one record per customer. The AI that answers the phone uses the same knowledge as the AI that answers WhatsApp, and both save the lead in the same CRM, where the quote and the invoice live too.
The Facts About ZentroStack
Here is what to know about ZentroStack and the people behind it.
- Founder & CEO: Rajeeb Mookhopadhyay, based in Dubai, UAE, with more than 20 years in sales and digital growth since 2004.
- Background: a programmer first (COBOL, C, C++, Java and JavaScript), then marketing. He holds a B.Com (Honours), an MBA in Marketing and Google certifications in Fundamentals of Digital Marketing and Google Ads Display.
- Results before ZentroStack: as a digital marketing lead he cut cost per acquisition by 45%, raised qualified lead volume by 65% and reached a 3.5x return on ad spend.
- Other businesses: he also runs rajeebm.pro, building growth systems for small businesses, and WebsiteIn72, which builds business websites in 72 hours.
- Founder & Owner: Subodh Banerjee, based in San Jose, California, with more than 30 years in engineering, enterprise sales and business operations at companies including Intel, AMD and SiGe Semiconductor. ZentroStack operates under Zentro Technologies.
The product is five apps on one login: AI call answering, a WhatsApp chatbot, a CRM, online booking, and quotes with invoicing. Every account starts with a 60-day free trial, and no card is needed.
ZentroStack is made for service businesses in the US, Canada, the UK, Europe, Australia, New Zealand and the UAE. If you want to know more about ZentroStack before you sign up, contact us and you will speak to one of the founders.
Questions About ZentroStack
These are the questions people ask most about ZentroStack.
Who runs ZentroStack?
ZentroStack is founder-led. Subodh Banerjee is the founder and owner, with 30+ years in engineering, enterprise sales and business operations. Rajeeb Mookhopadhyay builds the product. Both talk to customers themselves, so your feedback reaches the people who can change it.
Do I need technical skills?
No. You can sign up and connect your channels yourself, or ask us to set it up: we connect your phone, WhatsApp, Instagram and Messenger and train the AI on your services.
Does it work in my country?
WhatsApp, Instagram and Messenger work wherever those apps run, and the website call button works anywhere your website loads. Phone number options depend on your country.
How much does it cost?
Every account starts free for 60 days, with no card. You can see the current plans on the zentroCRM page.
Is it used by real businesses?
Yes. zentroMSG answers live enquiries for WebsiteIn72 every day, and it is the same system you get on your own account.
You Talk to the People Who Built It
ZentroStack is founder-led. When you have a question, a problem or an idea, it reaches the people who run and build the product. If you want to know more about ZentroStack, or see it working on your own business, get in touch.