Publishing an app on the App Store and Google Play: what you really need to know before launching

Neto Pompeu —

Publishing an app on the App Store and Google Play: what you really need to know before launching

It's a question that comes up regularly in early conversations with businesses in French Guiana: «we'd like to make an app». Great idea — mobile now represents more than 70% of consumers' digital time. But behind the development itself sits a whole machinery — licenses, commissions, legal compliance, security, design — that many project owners discover along the way, often too late, and which can derail a project.

Here is what you really need to understand before launching an iOS or Android application in 2026.

1. Developer licenses: what you pay just to exist

To publish an app, neither Apple nor Google is free. Before writing the first useful line of code, you must pay for the right to publish.

Apple Developer Program
  • $99 USD per year, renewable annually
  • $299 per year if you're an enterprise that wants to publish internally (Enterprise Program)
  • Without this account, impossible to submit anything to the App Store
  • Account validation: 24 to 72 hours, sometimes more if Apple requests a D-U-N-S verification for organizations
Google Play Developer
  • $25 once, paid for life
  • More accessible entry
  • But Google strengthened identity and organization checks in 2024-2025: a personal account can no longer publish without having 12 internal testers for 14 days minimum on new registrations

In practice, you'll also need: an SSL/TLS certificate if your backend is custom, sometimes an Apple Enterprise account (DPLA), and the mandatory D-U-N-S registration to publish as an organization.

2. Commissions: what Apple and Google take from your revenue

This is the topic that surprises new developers the most. Every transaction that goes through the app (purchase, subscription, premium unlock) is subject to a commission.

Apple App Store
  • 30% standard on in-app purchases and subscriptions in year one
  • 15% from year two of subscription for the same user
  • 15% from the very first transaction if you're enrolled in the Small Business program (less than 1 million USD in annual revenue). You must actively apply — it's not automatic.
  • 0% if your app is entirely free (no IAP, no subscription)
Google Play Store
  • Same tiers: 30% standard, 15% on the first 1 million USD of annual revenue
  • Limited option to use third-party payment in some countries (South Korea, India) but with commissions still at 11-26%

Key takeaway: if you charge €4.99 for a monthly subscription, you take home about €3.49 in year one (30%), then €4.24 in year two (15%). The 30% must be built into your business model from the start, otherwise your margin evaporates.

Extra surprise: Apple and Google take their commission before VAT is computed. You charge €4.99 incl. VAT to the user, and they pay 70% on the ex-VAT base. You need to understand the flows to avoid bad accounting surprises.

3. Legal: 175 countries, 175 regulations

Your app will potentially be available in 175 countries. Every country has its rules, and you are responsible for compliance.

Europe: GDPR
  • Privacy Policy mandatory, accessible before install and in-app
  • Explicit consent for personal data collection
  • User rights: access, rectification, erasure, portability, objection
  • DPO (Data Protection Officer) if you process data at scale
  • DPA (Data Processing Agreement) with each subprocessor: Firebase, AWS, Stripe, etc.
  • Penalties: up to €20 million or 4% of global revenue
Brazil: LGPD
  • Equivalent to GDPR with its own specifics
  • ANPD as the supervisory authority
  • DPA and processing register mandatory
California: CCPA
  • Right to know what data is collected
  • Right to request deletion
  • Explicit opt-out for data sale
Apple App Privacy
  • You must declare in App Store Connect all collected data, by category (identifiers, financial data, contacts, etc.)
  • Privacy Manifest (PrivacyInfo.xcprivacy file) required since 2024 — you must list «sensitive» APIs used (UserDefaults, file timestamps, etc.) and their reasons
  • Every third-party SDK must also ship its own Privacy Manifest
Google Play Data Safety
  • Data Safety section to fill in Google Play Console — equivalent of the Privacy Manifest
  • Declaration of data shared with third parties

A non-compliant app gets pulled from the stores. A GDPR fine can kill a company. This isn't something to handle lightly.

4. Security: protecting your users and yourself

Authentication
  • Sign in with Apple mandatory if you offer Google, Facebook or any other social login
  • 2FA recommended for apps with sensitive data
  • Secure token storage (Keychain on iOS, Keystore on Android)
Encryption
  • TLS 1.2 minimum (1.3 recommended) on all network communications
  • Encryption of sensitive data at rest on device
  • No plain-text password storage, ever
Standards to know
  • OWASP MASVS (Mobile Application Security Verification Standard): the mobile security reference
  • NIST for general requirements
  • HIPAA if you handle medical data (US)
Security updates
  • Monitor CVEs on your dependencies (Firebase, Stripe, RevenueCat, etc.)
  • Have a rapid patch plan for critical vulnerabilities

5. UX and UI design: what makes people use (or not) your app

Apple Human Interface Guidelines (HIG)

Apple has a reference document (HIG) defining iOS design conventions: navigation, typography, spacing, animations, gestures. Your app must feel like an iOS app, not a website converted into one.

Material Design (Google)

Same on Android. Material 3 for modern versions.

Accessibility
  • VoiceOver (iOS) and TalkBack (Android) support — mandatory for the European public sector (Directive 2016/2102)
  • Sufficient contrast (WCAG AA minimum)
  • Dynamic font sizes
  • Touch targets ≥ 44 × 44 points

Bad UX means a 30-day retention rate that drops. A failed onboarding means 70% of users uninstall within 24 hours.

6. Maintenance: the hidden part of the budget

An app is not a website you leave running. It requires:

  • OS updates: iOS and Android release one major version per year. If you don't follow, your app breaks on new phones within 18-24 months.
  • New devices: new iPhones, new Android foldables, Dynamic Island, ProMotion — all adjustments to make.
  • API deprecations: Apple and Google regularly remove old APIs. If your app uses a removed API, it no longer compiles.
  • Third-party SDK updates: Firebase, Stripe, RevenueCat ship new versions every month.
  • User support: bug reports, feature requests, possible moderation.

As a general rule, count 15 to 25% of the initial development cost per year for the maintenance of a live app.

The real budget of an app

For a well-built native iOS app, with a backend, polished design, GDPR compliant, ready for the App Store:

  • Design (UX + UI + spec): 4 to 8 weeks
  • Development: 3 to 6 months depending on complexity
  • Backend, infra, security: 1 to 2 months
  • Testing, QA, submission: 2 to 4 weeks
  • Annual maintenance: 15-25% of initial cost

A serious app on a single OS (iOS or Android) rarely starts under €25,000. A multi-OS app well done, with full backend, is more like €60,000 to €200,000 depending on complexity. Be wary of €5,000 quotes: it's either an ultra-limited MVP, or a project that won't survive the first iOS update.

Our approach at Primo-Studio

We support businesses in French Guiana through the entire app cycle — from idea to publication, then through maintenance. Our own apps JamBoard (musicians), PixConsent (image rights management) and AutoCare (car maintenance) are on the App Store, multilingual, GDPR/LGPD/CCPA compliant, and keep evolving.

We can step in at different levels:

  • Audit / scoping of an app project you're driving yourself
  • Full development iOS / Android / cross-platform
  • Legal compliance: GDPR, LGPD, App Privacy, Data Safety
  • Store submission: App Store and Google Play, rejection handling, ASO optimization
  • Maintenance once the app is live

Going further

Got an app project?

Contact us. Whether it's an idea to validate, an MVP to scope or an existing app to take over, we start with a free exchange to understand your need and estimate what it really represents.