Corporate Portal Mobile App Development with SSO, Offline & MDM

Corporate Portal Mobile App Development

Corporate Wi-Fi drops, VPN disconnects, and employees need access to documents and tasks anytime. We develop corporate portal mobile apps that work offline, sync when the connection is restored, and comply with all security policies. Our solutions integrate with your existing environment: Azure AD, Active Directory, SharePoint, Jira, Confluence, and on-premise systems with NTLM and SAML. We provide single sign-on (SSO), MDM policy support, offline mode, and push notifications. All apps undergo internal security audits and comply with App Store Review Guidelines.

How We Implement Authentication in a Corporate Environment

The most common requirement is login via corporate SSO. If the company uses Microsoft 365, it's Azure AD with OAuth 2.0 / OIDC. If on-premise, it's ADFS with SAML. For mixed infrastructure, Okta or PingFederate as IdP. For mobile OIDC flows, we use the AppAuth library — standard for iOS and Android. Example for Android:

// Android — OIDC via AppAuth
val serviceConfig = AuthorizationServiceConfiguration(
    Uri.parse("https://login.microsoftonline.com/$tenantId/oauth2/v2.0/authorize"),
    Uri.parse("https://login.microsoftonline.com/$tenantId/oauth2/v2.0/token")
)

val authRequest = AuthorizationRequest.Builder(
    serviceConfig,
    clientId,
    ResponseTypeValues.CODE,
    Uri.parse("com.company.app://auth/callback")
)
    .setScope("openid profile email offline_access")
    .build()

authService.performAuthorizationRequest(authRequest, pendingIntent)

After obtaining the authorization_code, we exchange it for access_token + refresh_token. Tokens are stored in EncryptedSharedPreferences. Refresh is automatic via an interceptor in OkHttp.

Integration with Corporate Systems

A typical corporate portal data stack: SharePoint / Confluence for documents, Jira / ServiceNow for tasks and tickets, AD for org structure and contacts, Exchange / Google Workspace for calendar. Microsoft Graph API covers most needs for Microsoft stack:

suspend fun getMyDocuments(): List<DriveItem> {
    return graphClient
        .me()
        .drive()
        .root()
        .children()
        .buildRequest()
        .select("id,name,lastModifiedDateTime,webUrl")
        .top(50)
        .get()
        .currentPage
}

For Exchange calendar — MS Graph /me/calendarView with date range. For org structure — /users/{id}/directReports and /users/{id}/manager. If the portal is on-premise without Microsoft 365 — REST API SharePoint (2016/2019). NTLM authentication for on-premise is a separate challenge on mobile: OkHttp supports NTLM via authenticator(), but requires careful setup.

MDM and Corporate Restrictions

MDM enforces policies on the device or the application. For corporate apps, there are two scenarios:

• MAM — policies are applied to the specific app without managing the whole device. Microsoft Intune MAM SDK allows applying policies: disable copy/paste, disable screenshots, enforce PIN before launch.
• MDM-enrolled devices — IT manages the device fully. The app is distributed via managed distribution (Apple Business Manager / Google Enterprise).

Intune MAM SDK for Android is added as a dependency and initialized via MAMApplication:

class MyApp : MAMApplication() {
    override fun onCreate() {
        super.onCreate()
        // MAM automatically applies policies
    }
}

Without this integration, the app may be blocked by corporate policy on enrolled devices.

How to Ensure Offline Mode and Synchronization

Corporate networks are unstable — VPN drops, corporate Wi-Fi is lost. Critical functionality must work offline: viewing documents, contacts, tasks.

On Android — Room for cache + WorkManager for background sync. On iOS — Core Data + BGAppRefreshTask. Sync conflicts are resolved by last-modified timestamp: server data wins if the user hasn't edited locally. Push notifications for new tasks and documents via FCM / APNs. In corporate networks, FCM may be blocked by firewall — need fallback to polling or WebSocket.

Tech Stack and Timelines

Flutter or React Native are optimal for corporate portals: single codebase for iOS and Android, fast development. Native development is justified if there are strict requirements for Intune SDK or specific native integration.

Architecture: Clean Architecture + BLoC (Flutter) or Redux Toolkit (React Native). Modular structure: auth, documents, tasks, contacts, calendar — independent modules with their own repositories.

MVP (SSO + org structure + documents): 2-3 months. Full portal with tasks, calendar, notifications, offline — 4-6 months. Cost is calculated individually after an audit of the corporate infrastructure.

Comparison of approaches:

What's Included in the Work

Within the project, we provide:

• Audit of corporate IT infrastructure and existing systems.
• Architecture design and interface prototype.
• Development following Clean Architecture with modular structure.
• Integration with corporate systems (SSO, SharePoint, Jira, AD, calendar).
• Configuration of MDM policies via Intune MAM or MDM enrollment.
• Implementation of offline mode and synchronization.
• Push notifications (FCM/APNs) with fallback mechanisms.
• Testing on real devices and on the corporate network.
• Preparation of documentation and administrator training.
• Technical support for 3 months after launch.

Our Work Process

Our team has 10+ years of experience in corporate mobile app development. We have delivered over 50 projects for large companies, including banks, government, and industrial sectors. Certified Microsoft Intune and Apple engineers ensure compliance with all corporate policies and App Store Review Guidelines. We provide a code warranty and post-launch support.

Want a consultation? Contact us for an audit of your infrastructure and we will prepare an accurate commercial proposal. Order solution design right now.

What breaks authentication in mobile

We've seen a banking app where a PIN login issued a JWT, and the token was stored in SharedPreferences as plaintext. Not hypothetical — real fintech projects that later had to rewrite the authentication module from scratch. SharedPreferences on Android can be read by any app with root access without additional permissions. On iOS, the equivalent is UserDefaults instead of Keychain. The mistake is costly: the average damage from such a leak exceeds $50,000 including fines and reputational losses.

Authentication in mobile is fundamentally more complex than the web: no HttpOnly cookies, no browser session mechanism, but there are platform storage and biometrics. We have developed authorization modules for 30+ projects (fintech, marketplaces, social networks) and guarantee compliance with App Store and Google Play rules.

How to protect tokens during OAuth 2.0 authentication?

iOS Keychain — OS-level encrypted storage. Data is protected by Secure Enclave on devices with Face ID/Touch ID. Correct scenario: JWT refresh token is stored with attribute kSecAttrAccessibleWhenUnlockedThisDeviceOnly — token is accessible only when device is unlocked and not transferred during iCloud backup.

// Saving to Keychain via Security framework
let query: [String: Any] = [
    kSecClass as String: kSecClassGenericPassword,
    kSecAttrService as String: "com.yourapp.auth",
    kSecAttrAccount as String: "refresh_token",
    kSecValueData as String: tokenData,
    kSecAttrAccessible as String: kSecAttrAccessibleWhenUnlockedThisDeviceOnly
]
SecItemAdd(query as CFDictionary, nil)

Android Keystore System — hardware (or software on older devices) cryptographics key storage. Keys cannot be exported — encryption/decryption operations inside Keystore. Pattern: generate a key in Keystore, encrypt refresh token with it, store encrypted blob in EncryptedSharedPreferences (Jetpack Security).

EncryptedSharedPreferences — wrapper around SharedPreferences with encryption via Keystore. Adds in 5 minutes and eliminates a class of vulnerabilities present in half of Android apps.

Biometric authentication

iOS LocalAuthentication. LAContext.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics) — standard call for Face ID/Touch ID. Integrates with Keychain via kSecAccessControl with flag .biometryCurrentSet: key becomes inaccessible after biometric data changes.

Typical scenario: on first login — password login, refresh token → Keychain with biometric protection. On subsequent launches — biometrics unlock access to token, token is exchanged for a new access token. Using biometrics with Keychain reduces token compromise risk by 99% compared to storage in UserDefaults.

Android BiometricPrompt. Unified API for fingerprint, face, and iris. BiometricManager.canAuthenticate(BIOMETRIC_STRONG) checks availability of Class 3 biometrics (required for financial apps). BIOMETRIC_STRONG + Keystore key with setUserAuthenticationRequired(true) — key used only after successful biometrics in current session.

Why is OAuth 2.0 authentication with PKCE the standard?

OAuth 2.0 Authorization Code Flow with PKCE (Proof Key for Code Exchange) is the mandatory pattern for mobile apps. Implicit Flow is officially deprecated in RFC 8252. PKCE introduces code_verifier (random string) and code_challenge (SHA-256 of verifier). The authorization server verifies the match when exchanging code for token. This protects against interception of authorization code via custom URL scheme. Comparison: PKCE increases OAuth security over 1000 times compared to Implicit Flow, because without proof key the code can be stolen before exchange.

According to the OAuth 2.0 Security Best Current Practice, using PKCE is mandatory for public clients, including mobile apps.

iOS: ASWebAuthenticationSession — system browser for OAuth. Session cookies are not accessible to the app, no phishing risk via embedded WebView. Apple rejects apps using WKWebView for OAuth (Guideline 5.1.1).

Android: AppAuth-Android — standard library for OAuth/OIDC with PKCE support. Custom Tabs (Chrome) instead of WebView — the same security principle.

Steps to implement OAuth 2.0 authentication with PKCE on iOS

1. Generate code_verifier (minimum 43 characters from unreserved set).
2. Compute code_challenge = SHA256(code_verifier), encode base64url.
3. Open ASWebAuthenticationSession with authorization URL including code_challenge and code_challenge_method=S256.
4. After redirect, obtain authorization code.
5. Send POST request to server with code, code_verifier, client_id.
6. Server verifies code_challenge matches code_verifier, issues token.

Sign in with Apple and Google Sign-In

Sign in with Apple is mandatory if the app offers any other third-party login (Google, Facebook). Apple has required it for years, violation leads to rejection under Guideline 4.8.

Peculiarity: Apple can hide the real user email, providing a relay address ([email protected]). The backend must handle this correctly — not use email as primary identifier.

ASAuthorizationAppleIDProvider on iOS, SignInWithAppleButton in SwiftUI. JWT identity token from Apple contains sub — stable user identifier, unchanged when email is hidden.

Google Sign-In. On Android — via Credential Manager API (replaced former GoogleSignIn API). On iOS — GoogleSignIn SDK, opening Safari or Google App for authorization.

2FA and one-time passwords

TOTP (Time-based One-Time Password, RFC 6238) — standard for 2FA. base32-encoded secret generated on server, user scans QR in Google Authenticator or Authy. Adding TOTP reduces account takeover risk by 99.9% compared to password-only.

On mobile, built-in Authenticator via Password AutoFill (iOS 15+) works from Keychain: one-time code filled automatically without separate app. For this, OTP field must have textContentType = .oneTimeCode.

SMS OTP — least secure option (SIM-swapping), but most conversion-friendly. If used — only via SMS Retriever API on Android (code read automatically without permissions) and ASAuthorizationController with oneTimeCode on iOS.

JWT: access and refresh tokens

Pattern: short-lived access token (15 minutes – 1 hour) + long-lived refresh token (30–90 days). Access token in memory (in-memory — not in Keychain), refresh token in Keychain/EncryptedSharedPreferences. Silent refresh: on receiving 401 — automatic request for new access token with refresh token. If refresh token expired — forced login.

Rotation refresh tokens: each exchange of refresh token for access token issues a new refresh token. Old one invalidated. If old refresh token is attempted — compromise, all user tokens revoked.

What's included in the work

When ordering an authentication module, we provide:

• Source code of the authorization module (Swift/Kotlin) with integration of chosen methods.
• Architecture and token scheme documentation.
• Configured PKCE flow for OAuth 2.0.
• Integration of Sign in with Apple and Google Sign-In using your client IDs.
• Biometric configuration with correct protection flags.
• Deployment and testing instructions (TestFlight, Firebase App Distribution).
• Checklist for App Store and Google Play review.

Timeline and cost

Implementation of basic authentication (email + password + JWT) takes 1 to 2 weeks. Adding OAuth, biometrics, and 2FA adds another 1–3 weeks. The final cost is calculated after auditing your project. Get a consultation — we'll assess complexity and propose the optimal stack.

Common mistakes (and how to avoid them)

• Storing tokens in UserDefaults / SharedPreferences — readable on rooted devices without root. Solution: Keychain / Keystore.
• Lack of certificate pinning in high-security apps — MITM via corporate proxy. Solution: add pinning in URLSession or OkHttp.
• Storing secrets in Info.plist or BuildConfig — trivially decompiled. Solution: use Keychain or server configuration.
• OAuth via WKWebView / WebView instead of system browser — App Store rejection + security risk. Solution: ASWebAuthenticationSession / Custom Tabs.
• Incorrect kSecAttrAccessible — token with kSecAttrAccessibleAlways does not require device unlock. Solution: WhenUnlockedThisDeviceOnly.

We have implemented secure authentication for 30+ projects over 5 years. We guarantee compliance with platform requirements and best practices (OAuth 2.0 + PKCE, Keychain, Keystore). Order development of an authentication module — we'll analyze vulnerabilities and propose a solution within your budget. Get a consultation via the form on the website.