Questions on creating HA dashboard

Hi, I’m thinking to buy a android tablet and create a dashboard for my HA which is in Hassio. Before that, i have few questions and hopefully someone here can help me out,

  1. How to ensure the tablet is always on? As normally tablet/phone has auto screen off after X minutes of time.
  2. I came across few options in creating the dashboard like using AppDaemon and TileBoard. Based on my understanding on these options, all the setup/configuration are done in HA and I just need to use the browser in my tablet to load the url. Is this correct?
  3. If my understanding above is correct, how do i ensure the dashboard is always running in full screen mode? As the notification bar will always shown in browser with Android tablet.
  4. Do I need to provide constant power supply to my tablet?

Thanks in advance.