Results & Tradeoffs

Tradeoff: A single suggested replacement is narrower than a dropdown. That trade is wrong for a customer with strong brand preferences, which is why "other options" sits directly beneath the approve button rather than behind a menu.

Tradeoff: Fewer taps can mean more accidental approvals. The tap count is a property of the design, not evidence that it works. The undo window exists specifically to absorb that risk, and undo rate is the counter-metric I'd watch.

Measured after launch. Support contacts citing a wrong, missing, or unexpected item: down roughly 15 percent per 100 orders. Post-delivery refund requests citing price: down roughly 20 percent.

Solution

A notification-first substitution flow that reduces the common six-tap, app-launch path to a single lock-screen tap, states the cost of the swap before the customer commits to it, keeps an undo window open until checkout, and resolves automatically.

Approach

I moved the decision out of the app and into the notification. The push names both products, states the price difference, and gives a clock time instead of a ticking countdown, so it can be answered from a lock screen in one tap. The in-app screen became the fallback for people who want to look closer, not the primary interface.

I stacked the original item above the replacement instead of placing them side by side. Two columns look tidier in a screenshot, but at phone width they force the eye to compare two 44-pixel labels. Stacked with a downward arrow, one item visibly replaces the other, and the layout does the comparison instead of the reader.

I put the price difference in its own row directly above the primary button. Unexplained charges are the most common complaint in delivery app reviews, and a plus-fifty-cents stated before the tap turns a possible refund dispute into a two-second decision.

I designed the ignored path first. Four of the six states in the sheet involve the customer never responding, because that's the majority case for anything triggered by a notification. Expiry produces an automatic refund plus a plain-language notice, so silence resolves cleanly instead of becoming a surprise at the door.

Client

Grocery delivery platform (under NDA)

Role

Product Designer

3 month (2025)

Duration

When a personal shopper finds an item out of stock, the customer has about five minutes to answer and is usually at work, in a meeting, or driving. Most delivery apps treat this as a preference question. A vague push notification, a substitute picker buried three screens deep, and a price change that doesn't surface until checkout.

The item quietly disappears, the customer finds out at the door, and a refund lands with no explanation attached to it.

So the design problem isn't picking a replacement product. It's making a timed decision answerable by someone who isn't looking at their phone.

Challenge

Making Substitution Approval Simple

Decisions under a Deadline