Newbie Questions

[mettamatt]

Hello! I'm very excited to join the community and completed my first CM3/BoxyPixel build. Though I have a few questions:

• What happens if I leave my device on? Will it automatically turn off or suspend after a certain period of time?
  
• Is there a sleep mode, or is a full shutdown and startup the way to use it?
  
• Should I bother using the 'sleep' mode built into some of the GBA games, or does that no longer apply?
  
• How do I know how much charge the battery has? I noticed that the retroarch.cfg has a menu_battery_level_enable config setting, but I didn't where to look for the output. 
  
• Do I need to worry about disabling bluetooth and wifi for the CM3 since it doesn't have those features? I saw the settings in the Retropie menu and was curious if I should run that everyime I start the system? 
  
• What should I expect for battery life? 4 hours?
  
• Any other optimizations or best practices to be mindful to preserve battery life? 
  

Thanks in advance for your advice!