One TypeScript codebase, two app stores, and very often a backend you already have. That's how we built and
shipped Buddy to the App Store and Google Play — and we'll tell you up front if your app is one of the few
that genuinely needs fully native code.
We build iOS and Android apps from one Expo and React Native codebase, with EAS Build handling cloud builds
and signing credentials.
Proof: Buddy by Ahmeego is live on both stores, built as a new client for our existing Cloudflare Workers
backend with zero backend changes.
Store rules are designed in, not patched in: in-app account deletion on both stores, Google Play's Android
16 (API 36) target for new apps and updates from August 31, 2026, and store billing for digital goods.
Budget for store accounts: Apple's Developer Program is $99 a year; Google Play charges a one-time $25
registration fee.
Our published estimate for a focused mobile MVP is four to eight weeks. Scope discipline decides where in
that range you land.
Who this is for
Companies with a working web product whose customers keep asking for an app.
Founders who need an MVP in real users' hands to test a hypothesis, not a year-long build.
Businesses that need an internal app for field staff, sales teams or operations.
Teams whose existing app was abandoned by a previous developer and is falling behind store requirements.
If your app is built around live AR, complex Bluetooth hardware or high-performance graphics, a fully native
build may be the better call. Our app development page explains when
we recommend going native instead.
What's included
Scope diagnostic that cuts version one to the smallest thing that proves the idea.
iOS and Android apps from one TypeScript codebase, using native patterns on each platform.
Backend integration with your existing API and auth, or a new Cloudflare Workers backend with
D1, R2 and KV if you don't have one.
Sign-in with email, Google and Sign in with Apple, all mapping to the same account and
session.
Store-required features: in-app account deletion, privacy disclosures, and store billing for
digital goods.
Push notifications with a permission prompt that appears when the user understands why.
Crash and error monitoring wired in before the first tester installs the app.
Store listings and submission: screenshots, descriptions, privacy labels, reviewer notes and
a working demo account.
Handover: repository, build credentials and documentation in your accounts.
How we build an app
Scope diagnostic
What's the smallest version that proves the idea? We cut hard in week one; it's the biggest single factor in
cost and timeline.
Architecture
Reuse your existing backend and auth wherever possible. Where there isn't one, we default to Cloudflare
Workers with D1, R2 and KV, as described on our app development page.
Design for thumbs
Native patterns — haptics, pull-to-refresh, skeleton loaders, deep links — following Apple's Human Interface
Guidelines and Material Design rather than a shrunken website.
Build and test
TypeScript throughout, automated tests on business logic, and internal builds shared with your testers by
link from the first week through TestFlight and a Play closed testing track.
Store submission
Listings, screenshots, privacy disclosures, review notes and a demo account for reviewers. We handle
rejections and resubmissions.
Launch and iterate
Crash and error monitoring from day one, JavaScript fixes over the air, and native updates through regular
store releases. Then handoff to your team or an ongoing retainer.
Mistakes that delay app launches
Building a second backend for the app instead of reusing the one the web product already runs on.
No in-app account deletion, which is a predictable rejection on both stores.
Pricing digital purchases without accounting for store commission.
Submitting without a working reviewer demo account.
A new personal Play Console account with no closed test planned, so production access waits two weeks longer
than anyone expected.
Letting the target API level fall behind until the app quietly disappears for new Android users.
Asking for notification permission on first launch, before the user knows why they'd want it.
Privacy labels that leave out data collected by an analytics or crash SDK.
Why Expo and React Native
React Native lets one codebase target iOS, Android and the web, and the React Native team's own
getting-started guide
recommends starting new apps on a framework rather than assembling the native tooling yourself. Expo is that
framework for us. Since React Native 0.76, the
New Architecture
is enabled by default, which matters when you pick third-party native libraries: we check each one supports it.
EAS Build, Expo's hosted
build service, produces store-ready binaries in consistent cloud environments, can generate and manage Android
keystores and iOS certificates and provisioning profiles, and hands successful builds to EAS Submit for store
upload.
EAS Update ships
JavaScript, styling and asset fixes between store releases. Expo is explicit about the limit: changes to native
code, native dependencies, permissions or the Expo SDK version need a new binary through store review.
The business case is simple: one team, one codebase and one set of tests instead of two, and the option to share
logic with your web app. The trade-off is that you depend on the library ecosystem for native features, which is
why the scope diagnostic lists every native capability before we commit.
Apple's account-deletion rule says deactivation alone isn't enough, and outside highly regulated industries
you can't force people through a phone call or email to delete. Apps using Sign in with Apple should revoke
tokens through Apple's REST API. Buddy's own account deletion page is part of
that flow.
Apple's
App Review Guidelines
now let apps on the United States storefront include buttons or links to purchase outside the app without a
special entitlement. Other regions still have separate rules, so we design the purchase flow per market.
Google Play lets you request an extension to November 1, 2026 for the API 36 deadline, but an extension is a
delay, not a plan. We upgrade the target as part of normal releases.
Pricing and timelines
Fixed-scope pricing after the scope diagnostic. Our
app development page publishes a four-to-eight-week estimate for a
focused mobile MVP; timeline depends more on scope discipline than engineering complexity. After launch you
choose: handoff with documentation and sessions, or an ongoing engineering retainer. Apple and Google fees are
paid to them directly, and the code is your IP unless we explicitly agree otherwise. No percentage fees,
consistent with our pricing page.
Platforms we work in
The mobile toolchain we ship with, from code to store listing.
Buddy is our AI Google Ads agent. It lived in the browser for two years before we took it to mobile, and the
architecture decision that made it shippable in weeks was this: the app is just a new client for the backend we
already had. The Expo app talks to the same Cloudflare Workers API and agent orchestrator as the web version,
with zero backend changes. Accounts carry over automatically — sign in with Google or Apple and your credits,
chat history and connected ad accounts are already there.
Native-only work in the store builds included:
Sign in with Apple, verified against Apple's public keys on our Workers backend and minting
the same session as Google sign-in.
Push notifications, including a low-credits alert that reaches users when the app is closed.
Real PDF and CSV export of chats and audits through the system share sheet.
In-app purchases of credit packs through each store's billing system, with balances updating
live across web and mobile.
A camera-first Creative Validator that checks ad assets against 50+ platform specs.
The iOS build cleared App Store review on July 10, 2026, and the Android app is on Google Play:
App Store
·
Google Play.
Launch write-up
Buddy goes mobile
The full story of taking a web agent to iOS and Android, including what changed and what didn't.
Our published estimate is four to eight weeks for a focused MVP. Larger scopes take longer. The biggest
variable is how much you're willing to cut from version one.
How much does it cost to publish on the App Store and Google Play?
Apple's Developer Program is $99 per membership year and Google Play has a one-time $25 registration fee.
Apple also takes 30% of digital goods sold in-app, or 15% under its Small Business Program for developers with
up to $1 million in prior-year proceeds.
Should we build with React Native or fully native?
React Native via Expo for most apps: one codebase, faster delivery, code shared with the web. Fully native
when the app depends on deep hardware integration such as live AR or complex Bluetooth.
Can the app use our existing backend?
Usually, yes, and it's the fastest route. Buddy's mobile app runs on the same Cloudflare Workers backend as
the web version with zero backend changes.
Can you update the app without waiting for App Store review?
JavaScript, styling and asset fixes can ship over the air with EAS Update. Anything that changes native code,
native dependencies, permissions or the Expo SDK version needs a new build through store review.
Why does Google Play make us run a closed test first?
Personal developer accounts created after November 13, 2023 must run a closed test with at least 12 opted-in
testers for 14 consecutive days before applying for production access. We plan the test into the schedule from
week one.
Do you handle App Store submission and rejections?
Yes: listings, screenshots, privacy disclosures, reviewer notes and demo accounts, plus any back-and-forth
with review. Account deletion and target API requirements are built in to avoid the common rejections.
Tell us about your app
What should the app do, who is it for, and do you already have a web product or backend?
John, Kristy, or Sandeep will reply.One of the three of us will respond personally within 1 business day. No SDR queue.
Message received.
One of us will reply directly within one business day. While you wait, run a free
Buddy audit on your account.
Top 25 references
The primary sources, standards, research, and tools we rely on for this work. Every link was checked on
2026-10-11. We aren't affiliated with these publishers unless noted.
Official documentation
App Review Guidelines— Apple Developer The full rulebook for App Store approval, including in-app purchase rules and the U.S. storefront exception
for external purchase links.
App Store Small Business Program— Apple Developer The 15% commission for developers with up to $1 million in prior-year proceeds, and how to enroll.
App privacy details on the App Store— Apple Developer What the privacy 'nutrition label' requires you to disclose, including data collected by
third-party SDKs.
Human Interface Guidelines— Apple Developer Apple's design rules for navigation, controls and permissions that reviewers expect an app to
follow.
Sign in with Apple (HIG)— Apple Developer Button, placement and flow requirements for Sign in with Apple.
Payments policy— Play Console Help When Google Play's billing system is required for digital goods and what the exceptions are.
EAS Build— Expo Documentation Expo's hosted build service for signed iOS and Android binaries, including managed credentials.
Submit to app stores— Expo Documentation How EAS Submit uploads finished builds to App Store Connect and Google Play from the command line or
CI.
EAS Update— Expo Documentation Over-the-air JavaScript updates between store releases, and the native-change limits that still need
review.
Push notifications overview— Expo Documentation How Expo push tokens, APNs and FCM fit together, and what needs a physical device to test.
Get Started with React Native— React Native The React Native team's recommendation to start new apps on a framework such as Expo rather than
wiring native tooling yourself.
About the New Architecture— React Native Explains the New Architecture, enabled by default since React Native 0.76, and what it changes for native
modules.
Standards & policy
OWASP MASVS— OWASP Mobile Application Security The industry standard for mobile app security requirements: storage, crypto, auth, network and
privacy.
OWASP MASTG— OWASP Mobile Application Security The testing guide that turns MASVS requirements into concrete checks for iOS and Android builds.
Research & studies
State of React Native 2025— State of React Native Community survey of React Native developers on tooling, pain points and which libraries they rely on.
Leading tools
TestFlight— Apple Developer Apple's beta distribution for internal and external testers before App Store release.
Sentry for React Native— Sentry Docs Crash and error monitoring setup for Expo and React Native, including source maps for over-the-air
updates.
Expert guides
Material Design 3— Google Android's design system, the counterpart to Apple's HIG for making the Android build feel
native.
AI disclosure: This page was drafted with AI assistance and edited by a human. Third-party facts
link to the official source they came from (checked 2026-10-11); platform names and logos belong to their owners
and do not imply a partnership or endorsement.
