1. what is singleton 2. difference between singleton and static 3. shared preferences.can we use const and static instead of shared preferences 4. difference shared prefe and const and static 5. transfer data from service to activity 6. transfer data from frgament to activity 7. explicit intent vs implicit intent 8. async await and thread.run when u use 9. different modes of sharing data 10. How to transfer data between two apps 11. content providers 12. how to transfer data between two apps 13. method overriding 14. source control used - TFS and GIT 15.keyword outer 16. how to check app crash due to low memory and retain the fragment 17.limitations on background services in new APIs 18. Activity Lifecycle 19. which event is called if there is change in text
