Activity tracker: yes; battery life: 24 hour based on usage; compatibility: android os 4.4+ or iphone 5/ios 8.2+; connectivity: bluetooth smart enabled / 4.1 low energy, wi-fi 802.11 b/g/n Display size: 1.5" active area diameter; sleep monitor: yes; interchangeable: yes; notifications: yes; touchscreen: yes; in the box: wireless charger (usb type) / quick start guide Quartz Movement Case Diameter: 44.5mm Water resistant to 10m (33ft): in general, withstands splashes and rain, but not immersion