Activity Cycle : 

The State of the Android process is determined by status of the activities and components that make up the applications that it hosts. The current state of the activity is determined by Activity Stack.


As shown in the diagram, new activities are pushed on the top of the stack when they are started. The current activity is at the top of the stack until it is pushed down the stack by the new activity , or popped of the stack when it exists or the user navigates to the previous activity.



WWDC 18 Announcement:


In brief, here are some of the major announcements for iOS:

  • iOS 12 will come with ARKit 2 that adds several improvements including shared experiences, 3D object detection, and persistent experiences. With shared experiences, you can now share the same AR space with other devices. This empowers developers to create an even more engaging AR experience for their users.

  • Apple also introduced a new open file format known as USDZ (Universal Scene Description) for AR objects.

  • Siri has been improved to let you create shortcuts. You can now use a built-in Shortcut app to create the shortcut. For example, you can create a phase "Heading home" as a shortcut. And you can define a series of actions to associate with this shortcut. Say, send a message to mum, play your favorite song and show you the next bus schedule. So, next time when you speak "Heading home" to Siri, the assistant will help you execute the predefined actions.

  • Facetime now supports group call (up to 32 people)!

  • Messages app now comes with more Animoji, plus you can define your own Memoji.

  • Apple introduced a new tool for Machine Learning training called Create ML. And you can train your models using Playgrounds.

  • Is Apple planning to merge macOS and iOS? The answer is No!

  • But Apple is working on a multi-year project to bring UIKit to macOS. This will make developers easier to port their iOS apps to macOS. You can expect this will come to developers in 2019.

This is just a recap for some of the highlights specifically for iOS 12. For the full keynote, you can watch it here.


Apple introducing Health record API for developers : 


For all of the news that Apple managed to cram into today’s 135-minute(!) WWDC keynote this morning, the event was actually pretty light on health care updates. It was a bit of a surprise, given how much of a focus the company has put on the space at past events.

Apple did announce an interesting health tidbit today on its website today — something that likely just got squeezed out of keynote the event late in the game. Starting this fall, the company will open up health record data to third-party iOS apps through a new API. The feature will make it possible for users to share health data from more than 500 hospitals/clinics with third-party apps


The CloudKit Framework is one of the more remarkable developer feature available in iOS SDK solely because  of the was with which it allows for the structured storage and retrieval of data on Apple's iCloud database servers. 


Mobile App Ecosystem 


BLE devices Overview: 


Bluetooth Low Energy (Bluetooth LE, colloquially BLE, formerly marketed as Bluetooth Smart) is a wireless personal area network technology designed and marketed by the Bluetooth Special Interest Group (Bluetooth SIG) aimed at novel applications in the healthcare, fitness, beacons, security, and home entertainment industries. Compared to Classic Bluetooth, Bluetooth Low Energy is intended to provide considerably reduced power consumption and cost while maintaining a similar communication range 



Borrowing from the original Bluetooth specification, the Bluetooth SIG defines several profiles — specifications for how a device works in a particular application — for low energy devices. Manufacturers are expected to implement the appropriate specifications for their device in order to ensure compatibility. A device may contain implementations of multiple profiles.

Majority of current low energy application profiles is based on the generic attribute profile (GATT), a general specification for sending and receiving short pieces of data known as attributes over a low energy link. Bluetooth mesh profile is the exception to this rule as it is based on General Access Profile (GAP


There are many profiles for Bluetooth Low Energy devices in healthcare applications. The Continua Health Alliance consortium promotes these in cooperation with the Bluetooth SIG.

  • BLP (Blood Pressure Profile) — for blood pressure measurement.
  • HTP (Health Thermometer Profile) — for medical temperature measurement devices.
  • GLP (Glucose Profile) — for blood glucose monitors.
  • CGMP (Continuous Glucose Monitor Profile)


Profiles for sporting and fitness accessories include:

  • BCS (Body Composition Service)
  • CSCP (Cycling Speed and Cadence Profile) — for sensors attached to a bicycle or exercise bike to measure cadence and wheel speed.
  • CPP (Cycling Power Profile)
  • HRP (Heart Rate Profile) — for devices which measure heart rate
  • LNP (Location and Navigation Profile)
  • RSCP (Running Speed and Cadence Profile)
  • WSP (Weight Scale Profile)