Apple Watch Series 4 (40mm)

Design and Display

• Case Size: 40mm
• Case Material: Aluminum or Stainless Steel options
• Display: LTPO OLED Retina display with Force Touch
• Resolution: 324 x 394 pixels
• Always-On Display: Not available (introduced in Series 5)
• Glass:
  • Ion-X strengthened glass (Aluminum models)
  • Sapphire crystal (Stainless Steel models)
• Water Resistance: Up to 50 meters (swim-proof)

Performance

• Processor: S4 dual-core 64-bit processor
• GPU: Apple-designed GPU
• Chip: W3 wireless chip for enhanced connectivity
• Storage: 16GB internal storage
• Operating System: watchOS (upgradable to the latest supported version)

Health and Fitness Features

• Heart Monitoring:
  • Second-generation optical heart sensor
  • Electrical heart sensor (ECG app capability)
• Fall Detection: Enabled with emergency SOS functionality
• Activity Tracking: Tracks steps, calories burned, distance, and more
• Workout Tracking: Preloaded with multiple workout modes, including running, cycling, swimming, and yoga
• High and Low Heart Rate Notifications
• Irregular Rhythm Notification: Alerts for potential atrial fibrillation
• Breathe App: Guides mindfulness and stress relief

Connectivity

• GPS + Cellular Models: Available (cellular models support LTE and UMTS)
• Bluetooth: Version 5.0
• Wi-Fi: 802.11b/g/n, 2.4GHz
• NFC: Supports Apple Pay
• Compass: Not available (introduced in Series 5)

Battery

• Battery Life: Up to 18 hours (all-day battery life)
• Charging: Magnetic charging cable included

Other Features

• Digital Crown: Redesigned with haptic feedback
• Speaker: 50% louder than Series 3
• Microphone: Improved placement for better voice clarity
• Siri: Built-in with voice commands and raise-to-speak functionality
• Custom Watch Faces: Infograph, Modular, and others
• Haptic Feedback: Enhanced with the Digital Crown
• Emergency SOS: Includes international emergency calling (cellular models only)

Compatibility

• iPhone Compatibility: Requires iPhone 6 or later with iOS 12 or later