Since 2023Mitsui Cuisine
Member app connected to back-end systems
We built the member app's back end and connected it to the existing systems.
- Membership
- Existing systems
- Restaurant group
Member App Member app development Membership cards, points and coupons,
in your own brand's app.
Customers show a member barcode, earn and redeem points, claim coupons, check their tier and receive your push notifications in one app. Member, points and transaction data stay in your own membership system and match what store POS, e-commerce and CRM see.
Free requirements review · Reply within 1 business day · NDA available
JoinX experience
- projects delivered
- 520+
- clients served
- 220+
- years of development
- 10+
- legacy systems taken over
- 100+
What is a member app, and how does it differ from a LINE MINI App or a web member portal?
A member app is your brand's own app on the App Store and Google Play that brings membership cards, points, coupons, member tiers and push notifications into one place, with member and points data stored in your own membership system and synced with store POS, e-commerce and CRM. Compared with a LINE MINI App, a member app has to be downloaded, but it can use push notifications, location, Bluetooth and other phone features, and it is your own branded entry point. A web member portal needs no download, but notifications and phone features are more limited. A member app suits brands with frequent repeat customers that want their own member channel; to lower the barrier first, start with a LINE MINI App, and both can share one membership system.
Real projects Member app and membership system work
Member apps for restaurants, department stores and auto brands: we have built them.
Below are member app, points and membership integration projects we built and maintain, from new builds and connections to existing systems to long-term operations after launch.
Since 2022Multi-brand restaurant group
Group dining member app
Development of the group's dining member app.
- Member app
- Multi-brand
- Restaurant group
Since 2025Department store group
Member app point top-ups and redemption
Topping up and redeeming member points, with ongoing maintenance and changes after launch plus yearly vulnerability scans and report review.
- Points
- Member app
- Long-term maintenance
2026China Motor Corporation
China Motor owner app
We handle the owner app and consolidated the systems behind owner services.
- Owner app
- Consolidation
- Automotive
Automotive group
Cross-brand membership with single sign-on
Rental, car-sharing, charging and other services brought under one membership, connected across brands with single sign-on (SSO).
- Membership
- SSO
- Multi-brand
2026Food-tech company
Convenience-store points and staff meal ordering app
Convenience-store loyalty point integration (earning and redeeming) and a meal pre-ordering app for company staff, with the app and web version sharing one back end.
- Loyalty points
- Pre-ordering
- Shared back end
* Projects without a client name are described by industry under confidentiality agreements.
Features Common member app features
From membership cards to push, all data returns to one membership system.
Features can launch in phases. Decide first which system is the source of truth for members, points and transactions, so new features never create a copy of the data that does not match.
Membership card
Sign-up, sign-in and a member barcode recognised at checkout, with one member record across stores and online.
Points
Earn, redeem, top up and exchange points, with a traceable history that reconciles with your POS.
Coupons
Issue, claim and redeem coupons in store, with conditions and expiry dates, and no coupon used twice.
Member tiers
Tiers move up or down by spend or visits, each with its own points multiplier and exclusive offers.
Push notifications
Segmented pushes for campaigns, expiring points and coupon reminders, scheduled from the admin.
Existing systems
Members, points and transactions sync with POS, CRM and e-commerce through APIs, with no extra copy of the data.
Compare Member app vs LINE MINI App vs web member portal
Member app, LINE MINI App or web member portal?
All three can hold a membership card and points. They differ in how customers arrive, whether you can notify them and how many phone features you can use. The membership back end can be shared.
| Aspect | Member app | LINE MINI App | Web member portal |
|---|---|---|---|
| How customers start | Member app: Downloaded from the App Store or Google Play | LINE MINI App: Opened inside LINE, no download | Web member portal: Opened at a web address in the browser |
| Sign-in | Member app: Your own accounts, or third-party sign-in such as LINE or Apple | LINE MINI App: LINE account | Web member portal: Your own accounts, or third-party sign-in |
| Notifying customers | Member app: Push notifications, segmented by member criteria | LINE MINI App: Service notifications after a customer action, once verified | Web member portal: Mostly email and SMS |
| Phone features | Member app: Push, location, Bluetooth and more | LINE MINI App: Mostly what the web can use | Web member portal: Mostly what the web can use |
| Brand presence | Member app: Your own app icon and interface | LINE MINI App: Inside LINE, following LINE's design guidelines | Web member portal: Part of your website |
| Publishing | Member app: Apple and Google review | LINE MINI App: Verification requires LINE's review | Web member portal: No review |
| Best for | Member app: Brands with frequent repeat customers and their own member channel | LINE MINI App: Lowering the barrier and bringing members in through LINE | Web member portal: A supporting place to check points, orders and member details |
Process How we build it
Decide where the data lives before designing screens.
The screens are not the hard part. Members, points and transactions must match what stores and e-commerce see. Every phase ends with something you can accept.
- STEP 01
Requirements and data review
2–4 weeks
Agree which features come first, the membership and points rules, which system is the source of truth for members, points and transactions, and which POS, CRM and e-commerce systems to connect.
- STEP 02
Design and prototype
Depends on scope
Screens follow iOS and Android design guidelines. A clickable prototype is tried by store and marketing staff before sign-off.
- STEP 03
Build, integration and publishing
6 weeks–6 months
App, admin and APIs are built together, cross-platform with Flutter or React Native or native where needed, connected to POS, CRM and e-commerce, then submitted for Apple and Google review.
- STEP 04
Launch and operations
Ongoing
Monitor sign-in, points and redemption errors, and adjust for OS updates, security testing and campaigns. The same team stays responsible.
Pricing Price ranges
How much does a member app cost?
Estimates based on custom app and system projects in Taiwan in 2026. The final figure depends on the number of features, the systems to connect and the scope of the admin back office.
| Scope | Price range | Typical content | Timeline |
|---|---|---|---|
| Requirements review | NT$100k–300k | Review of features, membership rules and data flows, producing a comparable spec | 2–4 weeks |
| Basic member app | NT$500k–1.2M | Some of membership card, points or coupons, with a simple admin | 6–12 weeks |
| Full-featured | NT$1.2M–3M | Member tiers, points, coupons, push notifications, payments and a full admin | 3–6 months |
| Connect existing systems | NT$50k–200k per integration point | Data sync with POS, CRM or e-commerce | Depends on the other system's API |
App store account fees, push notifications and cloud hosting are billed by usage. Post-launch maintenance is a separate agreement.
FAQ Common questions
Member app development FAQ
How much does member app development cost?
Based on custom projects in Taiwan in 2026: a basic member app with some of membership card, points or coupons and a simple admin is about NT$500k–1.2M; member tiers, points, coupons, push notifications, payments and a full admin is about NT$1.2M–3M; each existing system connected (POS, CRM, e-commerce) is about NT$50k–200k. App store account fees, push and cloud hosting are extra.
How long does it take to build a member app?
A basic member app takes about 6–12 weeks and a full-featured one about 3–6 months, after a requirements review of about 2–4 weeks. The schedule also depends on whether your POS and CRM have APIs, and on Apple and Google review.
Should we build a member app or a LINE MINI App?
Build a member app if customers buy often, you need push notifications or you want your own member channel. If you want customers to join without downloading anything, start with a LINE MINI App. Both can share one membership system and admin, so the other channel can be added later.
Can a member app connect to our existing POS or CRM?
Yes. Members, points and transactions sync with your POS, CRM and e-commerce through APIs. Without an API, file exchange or an intermediary database can work, but reliability and maintenance cost are assessed first. Each integration point is about NT$50k–200k depending on the other system's API.
Where is member data stored?
Member, points and transaction data live in your own membership system and servers; the app is just one way to use that data. Store POS, e-commerce and the app then see the same data, and it stays with you if you add a LINE MINI App or change vendors.
Can you take over our existing member app?
Yes. Before taking over, we review the source code, architecture, servers and access to the Apple and Google developer accounts to confirm everything can be handed over, then decide whether to continue maintenance, rewrite in phases or consolidate systems.
Get started Start with membership and points
Tell us the first feature you want to give members.
No full spec needed. Tell us whether it is a membership card, points, coupons or push notifications, where member data lives today, which POS your stores use, and whether there is an existing member app to take over.
- 1A sales manager replies within 1 business day
- 2Sign an NDA first, then discuss your workflow and data
- 3We discuss workflow and scope first, and quote once the spec is clear