title: ios autolayout constraints to resize view for screen size
body: <p>I am new to ios development and still trying to get hang of autolayout. The problem that I am facing can be better explained with images below</p>
  
  <p><img src="https://i.stack.imgur.com/owop8.png" alt="App on Iphone 5 screen size 4 inch"></p>
  
  <p><img src="https://i.stack.imgur.com/81EHF.jpg" alt="App on iphone 4 screen size 3. inch"></p>
  
  <p>Now I am removing the "Login with a social network" on iphone 4. What I want is how to center the google plus icon between the "OR Label" and "Start without registering" button
  and it should also resize to fit between them.</p>
  
  <p>what kind of constraints does it need to achieve that. If someone can point me in the right direction that would be great help. I have been breaking my head over this entire day. Thanks.</p>