title: Undefined symbols for architecture armv7 using Cocoa Pods
body: <p>Have some trouble which makes me crazy for a long time. I'm using pods in my project. When I run on simulator, everything ok. Project builds and runs without errors. But when I try to run on my device I get errors like</p>
  
  <pre><code>Undefined symbols for architecture armv7:
  "_OBJC_CLASS_$_FBSession", referenced from:
    objc-class-ref in ITGShareMenu.o
  "_OBJC_CLASS_$_FBLoginView", referenced from:
    objc-class-ref in ITGShareMenu.o
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/lJwcj.png" alt="enter image description here"></p>
  
  <p>Why on simulator project launchs with no errors but on device it crashes? How can I fix it?
  Thanks for yours appropriate answers!</p>