An alternative to the home button.
You can create or remove two notifications in the notification drawer that can not be cleared by system.
One is for going to the home screen.Another is recent apps switcher.

(you can create three shortcuts:ToHomeRecente apps switcherDrop down the status bar.)

+I'm not sure it's compatible with all version of android.

2.2.2 add floating buttons(need root access)
2.2.12 add floating buttons(not root)