title: Login Session - Activities
body: <p>I have a login in my application. I want to know the best way to set a global session or equivalent that I can refer to from any activity so that they will know if a user is logged in. Also, so that other activities can get the user id to do database transactions.</p>
  
  <p>I don't want to use putExtra() as I will have to do it for every Intent I build across the application.</p>