Wainaina Thomas
Live PWAProduct DesignE-Commerce

Dill: One Place for All the Supermarket Deals Near You

Most people in Nairobi do their shopping at the same one or two supermarket branches — whichever ones are on their way home. But finding out what's actually on offer before you get there? That's weirdly hard. Some stores post deals on Instagram. Others hand out paper flyers at the door. Dill puts all of that into one simple screen, sorted by how much money you'll actually save.

Role

Product Designer & Builder

Timeline

Feb – May 2026

At a Glance15-Second Overview
B2C Mobile Web App

The Friction

Supermarket deals across Nairobi were fragmented between PDF flyers, Instagram stories and physical signs. Shoppers had to check 4 different sources just to compare basics before grocery day.

The Insight

Percentages distort value (10% off infant formula saves KSh 500, while 30% off matches saves KSh 15). Shoppers think in currency, not percentages, and only care about stores along their commute.

The Outcome

A fast mobile PWA ranking active deals strictly by net shillings saved, with hyper-local branch filtering, zero account walls and zero notification spam.

01 / The Context

Why Finding Deals Is Harder Than It Should Be

Every major supermarket chain in Nairobi — Naivas, Quickmart, Carrefour, Chandarana, Cleanshelf — runs real promotional discounts every single week. The problem isn't that deals don't exist. It's that finding them before you walk into the store is needlessly annoying.

Some stores post 10-slide Instagram carousels on Friday evenings. Others upload long PDF booklets to their websites that you can't search through. And some only print paper flyers that you see when you're already at the entrance.

If you want to compare prices between two stores across the street from each other, you end up jumping between social media apps and PDF viewers for 10 minutes. Dill was built to replace all that with one fast, simple screen.

02 / Discovery

How People Actually Shop

I talked to regular shoppers around Nairobi — people doing their weekly runs at Naivas, Quickmart, Carrefour — and two things kept coming up:

Behavior 01

Sunday Planning Routine

Most people plan their big grocery run on Sunday evening, before the work week starts. They want to quickly compare prices and figure out where to go.

Behavior 02

Nobody Wants Another App

People really push back against downloading a heavy app just to check a few deals. A fast website they can bookmark is what actually works.

03 / Core Insights

Two Things I Kept Coming Back To

Insight 01

People Calculate in Shillings, Not Percentages

A "30% OFF" sticker on a KSh 50 box of matches saves you KSh 15. A "10% OFF" deal on a KSh 5,000 tin of infant formula saves you KSh 500. Percentages hide what actually matters. So Dill ranks every deal by the real shillings you save — not the percentage.

Insight 02

People Only Care About Stores on Their Route

Shoppers don't want deals from stores across the city they'll never visit. Dill lets you pick the specific branches near your home and office and hides everything else.

04 / Product Principles

What Dill Doesn't Do (On Purpose)

I set four rules early on, and they've stayed:

01. No Forced Signups

No sign-up screens. You open Dill and see every deal immediately — no email, no phone number.

02. No Notification Spam

No daily spam. If you save a deal, you get one reminder two days before it ends. That's it.

03. No Gamified Urgency

No spinning wheels, fake timers or pressure tactics. Just honest prices.

04. No Sponsored Bias

Stores can't pay to push their deals to the top. The ranking is based purely on savings.

05 / UI Showcase

What It Looks Like

Clean screens that make it easy to spot what matters:

Feature 01

Pick Your Nearest Stores

Tap to select the branches near your home and work.

Feature 02

Deals Sorted by Real Savings

Every deal ranked by how much you'll actually save in shillings.

Feature 03

Search for What You Need

Search for "cooking oil" or "rice" to see prices compared across all nearby stores.

Feature 04

Clean, Readable Price Cards

Numbers lined up cleanly so prices are easy to compare at a glance.

06 / Live Prototype

Interactive Deal Savings Calculator

Pick some common items from a typical Nairobi grocery basket and see how much you'd save in a week:

Sample Grocery Basket

Weekly Staples Comparison

Live Simulation

Total Estimated Savings

KSh 1,050

~KSh 4,200 saved per month

07 / FAQ

Product Questions

Is Dill affiliated with any supermarket?

No. Dill is 100% independent. We aggregate publicly published promotions without store sponsorship or paid placement.

How are promotions verified?

Promotions are cross-referenced with public retailer flyer publications every morning. If a price is outdated, users can flag it directly on the card.

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