I tried using the sample code in this link but it seems outdated and it did not work. So what changes do I have to make and to what files to have my app start automatically
Additionally you can use an app like AutoStart if you dont want to modify the code, to launch an android application at startup: AutoStart - No root
Another approach is to use android.intent.action.USER_PRESENT
instead of android.intent.action.BOOT_COMPLETED
to avoid slow downs during the boot process. But this is only true
if the user has enabled the lock Screen - otherwise this intent is never broadcasted.
Reference blog - The Problem With Android’s ACTION_USER_PRESENT Intent