I want my app to be in the autostart list after installation.
I know when I install an app like (whatsapp) it goes automatically to the autostart list. I want my app
Few popular apps run in background without being killed during memory cleanup cycle (many of the popular OEMs customize the stack ROM for battery/memory optimization), because they are "White listed" by these manufactures. For your app you can whitelist it either manually (via corresponding "settings" for the devices) or pragmatically by redirecting users to the corresponding settings page to white list the app.
Please have a look for details here