One of the biggest annoyances of Android is when plugging into a PC or Mac, you have to manually find the 'Connected by USB' prompt and then select 'File transfer', since otherwise you get just get charging functions. This dance of swipes and taps takes 10 seconds every single time, but thanks to Juan Carlos Bagnell's discovery in each phone's Developer Options, it seems that you can set 'File transfer' as the default.
Really useful. Though if you haven't already enabled 'Developer Options' in your Android phone then you can do this by going into (typically) 'About phone' and then tapping repeatedly on 'Build number' until the OS confirms that you're now a 'developer'. Going back one level in Settings, you should see 'Developer options' as a new menu item and then you can proceed as shown in the video.
What a useful tip!
PS. Note that the 'charge only' behaviour is manufacturer dependent - not all Android phones have this as the default.