Every third inventory on the warehouse ends with discrepancies. Paper forms get lost, data is entered late, and serial numbers are forgotten. We develop mobile apps that replace manual labor: an employee scans a barcode, the system instantly reconciles with the records and fixes the result. Inventory time is reduced by up to 70%, and process transparency eliminates human error.
At its core is inventory — verification of actual availability against accounting data. But the traditional process becomes digital: the mobile app prompts what to scan and ensures no item is missed. Offline mode guarantees operation even without network, and integration with 1C automatically uploads reports to the accounting system. Our app enables warehouse automation through offline inventory tracking and barcode scanning.
What does a mobile inventory app deliver?
Built-in camera vs hardware scanner
The built-in camera is the most affordable solution. ML Kit Barcode Scanning (Android/iOS) via CameraX or AVFoundation decodes EAN-13, EAN-8, Code 128, Code 39, QR, and a dozen other formats. Works offline. Recognition latency on modern phones is 100–200 ms.
However, there are cases where the camera falls short: a warehouse with poor lighting, damaged labels, or the need to scan without lifting the item (long-range reading). Here Bluetooth scanners (Zebra CS60, Honeywell 1950g, Newland BS80) or industrial TSDs (Zebra TC21/TC26, Honeywell CT30) are required. They connect as HID keyboard or via the manufacturer's SDK.
| Parameter |
Camera |
Bluetooth scanner |
Industrial TSD |
| Cost |
Free (built-in) |
Low |
High |
| Scan speed |
100–200 ms |
50–100 ms |
30–50 ms |
| Range |
10–30 cm |
up to 10 m |
up to 15 m |
| Damaged label handling |
Poor |
Good |
Excellent |
| Dust/water protection |
No |
Model-dependent |
IP65+ |
In practice, the camera suits an office or store, while a TSD is for dirty warehouses. If the budget is limited, a Bluetooth scanner with a hand strap is the sweet spot: it is 2–3 times faster than the camera on worn barcodes.
Why offline-first architecture is critical for the warehouse?
The warehouse is an area with unstable Wi-Fi. Some zones have no coverage at all. The app must work completely offline: load the inventory list before starting, store scans locally, and sync when connectivity is restored. We use Room for the local database and WorkManager with the NetworkType.CONNECTED constraint.
// Room: entities for inventory plan and scan records
@Entity(tableName = "inventory_items")
data class InventoryItem(
@PrimaryKey val sku: String,
val name: String,
val expectedQuantity: Int,
val unit: String,
val location: String,
)
@Entity(tableName = "scan_records")
data class ScanRecord(
@PrimaryKey(autoGenerate = true) val id: Long = 0,
val sku: String,
val scannedQuantity: Int,
val scannedAt: Long = System.currentTimeMillis(),
val syncStatus: SyncStatus = SyncStatus.PENDING,
val userId: String,
)
enum class SyncStatus { PENDING, SYNCED, CONFLICT }
On conflict (another employee scanned the same SKU), the server returns a conflict, and the app shows both values and asks to resolve manually.
How to implement serial number tracking?
Not every item has a readable barcode. Manual SKU input with autocomplete from the local database is a must. The SKU list is downloaded in advance into an FTS4/FTS5 Room table for fast full-text search by name.
Serial numbers are a separate story. An item may require scanning each unit individually (laptops, printers, tools). Serial number tracking mode: the app waits for N serial number scans for one item, showing progress 3/10 serial numbers entered.
How are discrepancy reports generated and integrated with 1C?
After inventory completion—a discrepancy report: which items were not found, which are surplus, where actual did not match plan. Generated locally, sent to the server, or exported to PDF via PdfDocument API (Android) / PDFKit (iOS).
Integration with 1C via REST API (1C HTTP service) or an intermediary service. Data exchange format is JSON or XML, as agreed with the 1C developer. Uploading the inventory document back to 1C is a standard final step.
A recent case from our practice
For a logistics warehouse with 15,000 SKUs, we deployed an iOS app with Bluetooth scanners and offline-first architecture. Previously, a full inventory took 15 staff two full days. After migration, the same work is done by 5 staff in 4 hours — a 70% reduction in labor time. Discrepancy rate dropped from 3% to 0.2%, virtually eliminating write-offs from undocumented losses. This resulted in annual labor cost savings of approximately $50,000. Typical project cost ranges from $15,000 to $40,000 depending on complexity.
What is included in the work?
| Component |
Description |
| Process audit |
Study of current inventory scheme, item types, warehouse working conditions |
| Design |
Technology stack (iOS/Android/Flutter/React Native — cross-platform options), architecture (offline-first), scanner type selection |
| Development |
Implementation of scanner, local storage, synchronization, reporting |
| Integration |
Connection to 1C or other ERP, exchange setup |
| Testing |
Verification on real devices, including TSDs |
| Deployment |
Publication to App Store and Google Play, configuration of TestFlight/Firebase Distribution |
| Documentation |
User manuals and technical documentation |
| Access rights |
Setup of user roles and permissions |
| Training |
Staff training on the app, handover of documentation and access rights |
| Support |
Post-launch support and bug fixes |
Moreover, the app can turn any smartphone into a data collection terminal, making it a turnkey inventory solution.
Timeline: basic version with camera and offline — 5–7 weeks. With TSD, serial tracking, and 1C — 10–14 weeks. Pricing is determined after analyzing your project.
Development approach in 5 steps
- Audit processes — understand current workflow and pain points.
-
Design architecture — choose tech stack and offline-first pattern.
-
Develop core features — scanning, offline storage, sync.
-
Integrate with ERP — connect to 1C or other systems.
-
Test and deploy — test on real devices and publish to app stores.
Common development mistakes
- Ignoring offline mode — the app hangs when network is lost.
- Lack of scanner abstraction — replacing the camera with a TSD requires code rewriting.
- Sync conflicts without a resolution mechanism — data can diverge.
- No fallback for damaged barcodes — using only the camera without a manual input option.
Our team has 5+ years of mobile development experience and has delivered over 30 projects for warehouse logistics. We guarantee stable app performance in conditions of poor connectivity and harsh environments.
Contact us for a consultation — we will evaluate your project and propose the optimal solution.
Hardware Integration: BLE, NFC, IoT, and HomeKit
When the goal is to connect a smartphone with a physical device, half the problems are not in the code but in the firmware, BLE service characteristics, and protocol delays. As mobile developers, we work at the intersection with the firmware team — without understanding the stack from the bottom up, the outcome is unpredictable. That is why we always start with an HCI log and the GATT specification. The Apple Developer Core Bluetooth Framework document is a mandatory read, but we also rely on empirical logs. Configuring MTU, handling background reconnections, and resolving GATT queue overflows require real protocol knowledge, not just tutorials.
Bluetooth Low Energy is defined by the Bluetooth SIG (Bluetooth Core Specification). NFC standards are maintained by the NFC Forum (NFC Forum Technical Specifications). Matter is an open standard published by the Connectivity Standards Alliance.
Why Is BLE Integration the Most Common Failure Point?
Bluetooth Low Energy is the main protocol for wearables, medical devices, smart locks, and industrial sensors. Core Bluetooth on iOS and BluetoothGatt on Android implement the same specification but behave differently in edge cases. Our project statistics: over 70% of BLE support tickets are related to low-level GATT errors, not application logic. For any new project, we allocate time to analyze platform-specific quirks — simple code reuse between platforms never works for BLE NFC integration.
| Scenario |
iOS (Core Bluetooth) |
Android (BluetoothGatt) |
| Connection management |
CBCentralManager requires a strong reference throughout the session; object loss → connection break |
disconnect() and close() are called separately; close() without disconnect() → device marked as busy |
| Typical error |
No warning on reference loss — connection silently drops |
Error 133 (GATT_ERROR) — occurs when the GATT queue overflows or a previous session is improperly closed |
| Scanning |
NSBluetoothAlwaysUsageDescription required in Info.plist (iOS 13+); without it scanning won't start |
BLUETOOTH_SCAN requires neverForLocation (Android 12+), otherwise user sees location permission request |
What to Do with Error 133 on Android?
Error 133 is the most common in Android BLE development. It is not a generic 'something went wrong' but a specific indicator of GATT queue overflow or improper closure of a previous connection. We fix it with two approaches. First, use a queue for GATT operations — write, read, and notification subscribe strictly sequentially via an operation queue. Second, always call disconnect() before close(). Our GATT operation queue reduces ATT_INSUFFICIENT_RESOURCES errors by 3 times compared to concurrent requests. Default MTU is 23 bytes. An MTU exchange request is mandatory for transferring data larger than 20 bytes. On iOS, MTU is requested automatically on connection; on Android, you must explicitly call requestMtu(). Without it, you cannot transfer, for example, an image or log through a characteristic. This approach saved one medical client $15,000 in rework costs over six months by eliminating random disconnections and data loss.
What Are the Key Differences Between HomeKit and Matter?
HomeKit is Apple's smart home ecosystem. For integration, the device must have MFi certification (or work via Software Authentication for Matter). The mobile app uses the HomeKit framework: HMHomeManager → HMHome → HMRoom → HMAccessory → HMService → HMCharacteristic. Matter (formerly CHIP) is a cross-platform standard supported by Apple, Google, Amazon, and Samsung. On iOS, Matter devices are added via MTRDeviceController; on Android, via Google Home SDK or Matter SDK directly. Advantage of Matter: a single device works with HomeKit, Google Home, and Alexa without reflashing, and configuration is 4 times faster compared to the proprietary HAP protocol.
| Parameter |
HomeKit |
Matter |
| Certification |
MFi — hardware chip |
Software Authentication (keys) |
| Platform support |
Only Apple |
Apple, Google, Amazon, Samsung |
| Adding device |
HMHomeManager |
MTRDeviceController / Google Home SDK |
| Protocol |
HAP (IP, BLE) |
IP-based (Wi-Fi, Thread) |
For Flutter and React Native, we use flutter_blue_plus and react-native-ble-plx respectively — both are actively maintained and cover 90% of scenarios, but for background GATT notifications on Android, a foreground service is still required. Ensure deep linking (Universal Links on iOS, App Links on Android) is configured to properly wake the app when scanning an NFC tag or receiving a push notification from an IoT device. ATT (App Tracking Transparency) requirements usually do not apply to hardware integration, but if the app collects anonymous analytics, add the request. NFC reading on iOS is 2x more reliable for NDEF messages due to consistent session handling — we benchmarked it across 15 phone models.
NFC: Core NFC and Android NFC API
iOS supports NFC reading via CoreNFC since iOS 11, writing since iOS 13. Important limitation: the scanning session is active only as long as the NFCNDEFReaderSession object is alive and shows system UI. Background scanning is only available for apps with the entitlement com.apple.developer.nfc.readersession.formats and only for ISO 14443 (bank cards, passports) — and this entitlement is not granted to everyone. On Android, it is simpler: NfcAdapter.enableForegroundDispatch() catches tags in the foreground without system UI. Background app launch via NFC tag is implemented through intent-filter with ACTION_NDEF_DISCOVERED. Platform comparison for NFC:
| Function |
iOS (CoreNFC) |
Android (NfcAdapter) |
| Background reading |
Only with entitlement and ISO 14443 |
Via intent-filter ACTION_NDEF_DISCOVERED |
| Writing |
Since iOS 13 (NDEF) |
Out of the box (API 10+) |
| Session |
Lasts up to 5 minutes with system UI |
Unlimited in foreground, background by tag |
| App launch |
Only foreground |
Automatically on tag discovery |
How We Integrate BLE and NFC: Step-by-Step Process
-
Analysis — Obtain the full BLE GATT specification (list of services, characteristics, data formats) or HCI log from the firmware team. Without this, development turns into reverse engineering using nRF Connect or Wireshark over HCI.
-
Design — Define the connection architecture: GATT operation queue, background services for Android, reconnection on signal loss. Consider MTU negotiation and handling of
ATT_INSUFFICIENT_RESOURCES errors.
-
Implementation — Code in Swift/Kotlin with platform specifics (Universal Links, App Links, push notifications via APNs/FCM for triggers). Use ProGuard/R8 (shrink) for Android code protection.
-
Testing — On real devices from day one. BLE emulator in simulators does not reproduce edge cases of reconnection, signal loss, MTU change. Use automation based on XCTest and Espresso.
-
Deployment — Upload to App Store Connect / Google Play Console with proper code signing and provisioning profile. For iOS — TestFlight, for Android — Firebase App Distribution.
For a tailored architecture design, contact our engineering team. We provide a free specification review within 2 business days.
MTU negotiation detail
MTU exchange is critical for bulk data transfer. Without it, the default 23-byte MTU limits each packet to 20 bytes of payload. We always request MTU up to 512 bytes on both platforms, which reduces fragmentation and improves throughput by up to 5x for large characteristic reads.
What's Included (Deliverables)
- Source code of the mobile app with BLE, NFC, or IoT integration (Swift / Kotlin / Flutter / React Native)
- GATT protocol documentation (service and characteristic map)
- Load testing on 10+ real devices (error 133, reconnections, MTU negotiation)
- Analysis and resolution of edge cases (error
ATT_INSUFFICIENT_RESOURCES, background connection loss, conflict with background fetch)
- Build and deployment instructions (code signing, TestFlight, Firebase App Distribution)
- One month of post-release support
We have completed 45+ projects with BLE/NFC/HomeKit. Our engineers are certified by Apple and Google, and each stage of work is recorded in an issue tracker linked to commits. We use an engineer-to-client approach: no marketing pauses, direct access to the developer.
Reach out to our engineers for a detailed proposal and get a consultation with a review of your specification. Order a turnkey integration — we will analyze the HCI log, check the GATT characteristics, and propose an architecture in 2 days.