Basic Android App

This is an Android app with 2 activities and one button. Application should call an existing WebApi web service function when the button is pressed. When result is received, application should share this result with one of messengers registered in the device. The same operation as you get when you select the text in mobile browser and press "Share". After that, the timer in main activity should start for 30 minutes, and each 30 seconds it should run the second function of web service. When 30 minutes end, the timer stops. When timer is working, the main activity should show the backward running timer counting 30 minutes to 0, and show when the second function was called last time. The application should be running even if the phone is locked, until the timer has stopped. The button on the main screen should then turn into "Cancel" button, and pressing it would stop the timer. The Settings activity should have 2 fields - one text and one dropdown, both should only save settings locally. It should work with API 19 (Android 4.4 and up). It should be native Java application.