(SEM VII) THEORY EXAMINATION 2024-25 MOBILE APPLICATION DEVELOPMENT FOR IOT

SECTION A — Very Short Answers (2 Marks Each)

a. Iterative Prototyping & Feedback Loops                    Continuous testing and user feedback

Early detection of design flaws                                      Reduces cost and design risk

b. Protocol for Low-Power IoT Device

MQTT or CoAP                                                             Lightweight, low bandwidth, energy efficient

c. Serial Terminal vs LCD Display                                   Serial terminal: Easy debugging, low cost

LCD: Stand-alone display, user-friendly, no PC required

d. Challenges of Interfacing Multiple Sensors              Limited I/O pins

Power management                                                     Data synchronization

Signal interference

e. Trade-offs in Customizing IoT Boards                      Performance vs cost

Power efficiency vs features                                        Scalability vs complexity

f. Wireless Communication Challenges (Large Scale)

Network congestion                                                    Interference

Latency                                                                        Power consumption

g. Storing Sensor Data in Google Sheet                     Use webhooks / IFTTT / Google Apps Script

Automate email alerts via triggers

h. Role of Webhook Services                                      Enable real-time data transfer

Trigger actions/events automatically

i. IoT Warehouse Monitoring Framework                  Sensors → Gateway → Cloud → Mobile App

Alerts, dashboards, analytics

j. Innovative Packaging Solutions                              Improves durability

Enhances usability                                                     Protects electronics from environment

SECTION B — Short Descriptive Answers (10 Marks)

a. Multi-Sensor Data Aggregation & Cloud Publishing

Read data from multiple sensors

Aggregate at edge device

Send to cloud (ThingSpeak, Firebase)

Edge preprocessing reduces latency & bandwidth

b. Blynk App with Temperature & Gas Sensors      Sensors → Microcontroller → Blynk cloud → Mobile app

Real-time sync via virtual pins                                Conflict handling using timestamps

c. Warehouse Monitoring Connection Diagram     Proper sensor placement

Wireless modules (Wi-Fi/LoRa)                               Redundant gateways for fault tolerance

d. Bluetooth vs Wi-Fi for IoT

e. Modularity in IoT Product Design                           Easy upgrades

Component replacement                                            Future technology compatibility

SECTION C — Fault Tolerance & Control (10 Marks)

a. Fault-Tolerant Sensor Display System                     Error detection

Backup sensors                                                           Retry mechanisms

Data buffering during communication loss

b. LED Control via Android APK                                  Mobile app sends commands

Microcontroller adjusts LED intensity                         Challenges: latency, synchronization, packet loss

SECTION D — Displays & Tracking Systems (10 Marks)

a. Temperature Display on 16×2 LCD                         Periodic refresh

Power-saving sleep modes                                         Filter faulty readings

b. GPS-Based IoT Tracking System                             GPS module + IoT device

Real-time location updates                                        Geofencing alerts