smoa/docs/reference/DEVICE-COMPATIBILITY.md

Device compatibility – Samsung Galaxy Z Fold5 (primary target)

This document describes SMOA compatibility with the Samsung Galaxy Z Fold5 (model SM-F946U1) as the primary target device, and what has been done to ensure the app works correctly on it.

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Required target (mandatory minimum)

Aspect	Required minimum
Device	Samsung Galaxy Z Fold5 (SM-F946U1) or equivalent (foldable, 4G/5G capable).
OS	Android 10 (API 29) or higher; primary target Android 16 (API 36).
App SDK	minSdk 24, targetSdk 34 (forward compatible on Android 16).
Network	Cellular (4G LTE or 5G NR) and/or Wi‑Fi; optional dual SIM.
Permissions	INTERNET, ACCESS_NETWORK_STATE; RECORD_AUDIO, CAMERA for meetings; READ_BASIC_PHONE_STATE optional for 5G MW detection.

Below minSdk 24 the app does not build. For full Android 16 behavior and testing, targetSdk 36 is recommended once the project upgrades the Android Gradle Plugin.

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Target device summary

Attribute	Value
Device	Samsung Galaxy Z Fold5 (SM-F946U1)
OS	Android 16, One UI 8.0
Cellular	4G LTE, 5G NR, 5G millimeter wave (5G MW) capable
Connectivity	Dual SIM (physical + eSIM), e.g. Dark Star + US Mobile
Security	SE for Android (Enforcing), Knox 3.12, DualDAR 1.8.0
Form factor	Foldable (cover screen + inner large screen)

App compatibility measures

1. SDK and API level

• Current: compileSdk = 34, targetSdk = 34, minSdk = 24 (see buildSrc/.../AppConfig.kt).
• Android 16 uses API level 36. The app is forward compatible: it runs on Android 16 with existing targetSdk 34; the system applies compatibility behavior.
• Recommendation for full Android 16 optimization: When upgrading the project’s Android Gradle Plugin (e.g. to 8.9+), set compileSdk = 36 and targetSdk = 36 and test against Android 16.

2. Foldable support

• FoldableStateManager (core/common) tracks folded vs unfolded state using a 600 dp width threshold, suitable for Z Fold5 (narrow cover vs wide inner screen).
• MainActivity calls foldableStateManager.updateFoldState(configuration) in onCreate and onConfigurationChanged, so fold/unfold updates the UI without requiring an activity recreate when combined with manifest configChanges.
• Manifest: MainActivity declares
  android:configChanges="orientation|screenSize|smallestScreenSize|screenLayout"
  so that fold/unfold and size changes are delivered to onConfigurationChanged and the activity is not recreated unnecessarily.
• MainScreen receives foldableStateManager and can adapt layout (e.g. list/detail, panels) for folded vs unfolded.
• PolicyManager supports a “lock on fold” option for security when the device is folded.

3. 4G LTE, 5G, and 5G MW (smart routing)

• ConnectivityManager (core/common):
  • getActiveTransportType() – WIFI, CELLULAR, VPN, ETHERNET, UNKNOWN.
  • getCellularGeneration() – when transport is CELLULAR, returns LTE_4G, NR_5G, or NR_5G_MW.
• Cellular generation logic:
  • LTE → LTE_4G.
  • NR (5G) + TelephonyDisplayInfo.overrideNetworkType == OVERRIDE_NETWORK_TYPE_NR_ADVANCED (value 5) → NR_5G_MW (millimeter wave); otherwise → NR_5G.
• Permissions: READ_BASIC_PHONE_STATE is declared (optional) to improve accuracy of 4G/5G/5G MW detection on API 29+. Not required for basic connectivity.
• Smart routing (e.g. MediaRoutingPolicy, NetworkPathSelector) uses transport type and cellular generation to prefer 5G / 5G MW over 4G where appropriate.

4. Dual SIM / multi-carrier

• The app uses the system’s default data network and active network capabilities via ConnectivityManager and NetworkCapabilities. It does not bind to a specific subscription ID.
• On dual-SIM devices (e.g. physical SIM + eSIM), the system chooses the active data subscription; SMOA’s connectivity and cellular generation logic apply to whichever subscription is currently used for data. No code changes are required for dual SIM per se.

5. Permissions (manifest)

• Network: INTERNET, ACCESS_NETWORK_STATE.
• Phone state (optional): READ_BASIC_PHONE_STATE (for 4G/5G/5G MW detection).
• Communications: RECORD_AUDIO, MODIFY_AUDIO_SETTINGS, CAMERA (meetings).
• Security: USE_BIOMETRIC, USE_FINGERPRINT, BIND_VPN_SERVICE.
• Storage: READ/WRITE_EXTERNAL_STORAGE with maxSdkVersion="32" where applicable.

6. Knox and SE Android

• The app does not use Knox APIs. It runs as a normal Android app; Knox/SE for Android enforce system policy (e.g. device attestation, MDM) independently.
• If future versions need Knox integration (e.g. Knox SDK for secure storage or VPN), the same device and OS support the required Knox API level (e.g. 39).

Testing on Z Fold5

• Fold/unfold: Open app on cover screen, unfold and fold; confirm layout updates and no unnecessary activity restarts.
• Network: Switch between Wi‑Fi and cellular; on cellular, confirm 4G vs 5G (and 5G+ where available) is reflected if you surface cellular generation in UI or logs.
• Dual SIM: Use one SIM for data, then switch default data to the other; confirm connectivity and routing still work.
• Meetings/WebRTC: Verify camera, microphone, and smart routing (e.g. path selection, codec selection) on both Wi‑Fi and 5G.

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Aspects which scale (client / device)

These dimensions scale with usage, device variety, or backend load. The required target above is the floor.

Aspect	What it scales with	How it scales
API level (minSdk / targetSdk)	Newer devices, Android 16+ features	Raise minSdk/targetSdk when dropping older OS support; use Build.VERSION.SDK_INT checks for optional APIs (e.g. 5G MW on API 31+).
Screen size / density	Folded vs unfolded, different devices	FoldableStateManager (600 dp threshold); responsive layouts; configChanges so fold/unfold doesn’t recreate Activity.
Network type	Wi‑Fi vs 4G vs 5G vs 5G MW	ConnectivityManager.getActiveTransportType() and getCellularGeneration(); smart routing and adaptive codecs use these.
Concurrent backend load	Number of devices syncing / pulling	Backend scales (see PROXMOX-VE-TEMPLATE-REQUIREMENTS.md); app uses rate limit and retries.
WebRTC sessions	Number of participants, video quality	Adaptive codec policy and connection-quality tier; TURN/signaling and backend infra scale with sessions.
Sync volume	Directory/orders/evidence/reports per device	Backend disk and DB; app queues and syncs by type; no fixed device-side limit.
Dual SIM / multi-carrier	Multiple subscriptions	App uses default data network; no per-SIM logic; scales to any number of SIMs as chosen by system.
Permissions	Features used (meetings, 5G detection)	Optional permissions (e.g. READ_BASIC_PHONE_STATE) scale with feature set; core works without them.

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References

• Smart routing / QoS: SMART-ROUTING-AND-QOS.md
• Media codecs (P2M, adaptive): MEDIA-CODECS-AND-P2M.md
• Backend sync: backend/README.md, backend/docs/BACKEND-GAPS-AND-ROADMAP.md
• Backend/infra scaling: PROXMOX-VE-TEMPLATE-REQUIREMENTS.md