How to build a coupon and local offers app

What a coupon and local offers app actually does

A local offers app connects shoppers with discounts they can use at a physical store or branch nearby. It differs from a promo-code website for online shopping, where a code is typed at checkout and the shop's own system checks it. In a local app, the shopper walks into a café, salon or shop, and someone at the counter has to accept the offer.

That makes it a two-sided product. Shoppers need to find an offer, understand its terms and know which branch to visit. Merchants need to publish offers, control how many are given out and confirm when one is actually used. If either side is weak, the product fails: shoppers stop opening an app with stale offers, and merchants stop publishing when they cannot tell what an offer produced.

A few terms are worth fixing early, because they become database entities and screen labels:

• Offer: what the merchant publishes, with its terms, duration, branch and any limit on the number of codes.
• Code (coupon): a unique identifier issued to one shopper for one offer.
• Reservation: the act of claiming a code before visiting, usually with an expiry.
• Redemption: the merchant's confirmation that a specific code was used at the counter.

Core features for shoppers and merchants

The core feature set splits cleanly by side. Each feature exists because one of the two users cannot complete their job without it:

Notice what is not on the list: payments, delivery and in-app chat. A local offers app does not need to process the purchase itself. The shopper pays at the counter as usual; the app's job is discovery, entitlement and confirmation. Leaving payments out also keeps the product away from regulated payment activity, which is a separate scope decision.

The business rules to decide before design

Coupon apps often disappoint because they were designed screen-first. The screens look complete, but nobody decided what happens when two shoppers reserve the last code at the same moment, or whether an expired reservation returns its code to the pool. Write these rules down before any interface work:

1. Who may publish. Only approved merchants, or anyone who signs up? Many local apps review merchant applications first.
2. Where the offer is valid. All branches, or a chosen branch? The shopper must see this before travelling.
3. How the offer is limited. By an end date, by a number of codes, or both. Decide whether a cap counts reservations or only redemptions.
4. How long a reservation holds. A reservation that never expires lets one person block a capped offer indefinitely.
5. Who confirms use. The shopper tapping "used" is not proof. Redemption should be confirmed by the merchant against a specific code.
6. What the reports count. Views, reservations and confirmed redemptions are three different numbers and should never be merged.

Each rule becomes a state, a permission or a database constraint. The detailed lifecycle of a code, including a state table and abuse prevention, is covered in our guide to coupon redemption codes.

How T-CODE brings both sides into one app

T-CODE, the offers and loyalty app FLUIDS designed and built in Flutter, is a working example of these rules in one mobile experience. Shoppers browse nearby stores and offers on a live map, filtered by city or category, and can open a store's location or contact details. Browsing is open to guests; reserving an offer code requires an account.

Once signed in, a shopper can save coupons and reserve an offer code. Reserved coupons are kept separate from codes already used, and reservations carry expiry information, so the shopper can see which offers are still available to use. Redemption is confirmed by the merchant, code by code, which separates interest in an offer from actual use.

On the merchant side, a business applies first and is reviewed and approved before a shop is created. The owner then sets up a store profile and branches, showing or hiding each branch as it is ready. Offers are published as time-limited or capped by a number of codes, and the cap is enforced rather than advisory. A dashboard brings together branches, offers, views, followers, used codes and conversion rate.

T-CODE also goes beyond coupons into loyalty: a points wallet with transaction history, QR-based customer identification, and point grants linked to a receipt. Those features are useful, but they are a second product layer. The T-CODE case study shows the full scope, and our article on building a loyalty points app explains that layer separately.

The technical building blocks

Under the screens, a coupon app is a small set of well-defined services. Getting these right matters more than the choice of framework:

• Identity and roles. Guests, shoppers, merchant owners and staff need different access. Role checks belong on the server, not only in the app.
• Catalogue data. Stores, branches with coordinates, categories, cities and offers, with a visibility flag so hidden branches and ended offers drop out of discovery.
• Reservation service. Issues codes, enforces caps and expiry in one transaction, and rejects requests once the limit is reached.
• Redemption service. Lets an authorised merchant look up a code and confirm it once; a second confirmation must fail.
• Maps and location. A map SDK, a nearby query on store coordinates, and a fallback to city selection when location permission is refused.
• Reporting. Counters and events for views, reservations and confirmed uses, aggregated per offer and per branch.

T-CODE uses Flutter for the mobile app and Supabase as its backend, a combination that suits a single codebase for iOS and Android with a Postgres database where constraints can enforce the rules. Whatever the stack, design Arabic-first with a correct right-to-left layout if your shoppers are in Saudi Arabia or the GCC, and plan for Apple App Store and Google Play review, which looks closely at location use and account deletion.

Shopper accounts and location data are personal data. In Saudi Arabia, the Personal Data Protection Law (PDPL) applies to how you collect, store and use them; confirm your obligations with qualified counsel. The location-based offers guide covers permissions and privacy in more depth.

What to put in the first release

A first release should prove that shoppers reserve offers and merchants confirm them. That loop is the product; everything else extends it. A sensible first scope looks like this:

• Map and list discovery with city and category filters, open to guests.
• Shopper accounts, saved coupons and code reservations with expiry.
• Merchant application and review, store profile and branches.
• Offers with a time limit or a code cap, enforced on the server.
• Redemption confirmed by the merchant, and a dashboard with honest counts.

Loyalty points, point-based orders and detailed staff permissions can follow once merchants are active. They add real value, but they also add accounting questions and counter workflows that are easier to design when you know how merchants use the first version.

Cost and timeline depend on how many of these workflows you include, how many roles you need, whether you build a separate admin panel, and how much reporting merchants expect. FLUIDS confirms both in a written proposal before development; see what determines app development cost and the MVP cost guide. For the wider context of two-sided products, read about our marketplace platform development and our work for e-commerce and retail.