"An invite-only gold catalogue, with WhatsApp as the front door."
A private catalogue for a small-scale gold jeweller, plus a custom app that handles OTP sign-in over WhatsApp instead of SMS.
A home-grown jewellery business wanted their collection online, but not publicly. Gold pricing and customer lists are not things you leave open to the internet.
So the catalogue is invite-gated. Customers get access, browse the collection, and save what they like. Everyone else sees the front door and nothing behind it.
Two problems. First, SMS OTP in India is slow, unreliable and billed per message — and this is a business where a customer who cannot get in simply phones instead, and the browsing data is lost.
Second, a jeweller does not want a login system to administer. It had to run itself.
I built the OTP flow on WhatsApp rather than SMS. It is instant, free, and lands somewhere the customer is already looking — with the shop's own profile picture next to it, which does more for trust than any security badge.
Behind the gate, the admin side shows which pieces each customer keeps coming back to. That turns a catalogue into a reason to pick up the phone.