title: How to create bubbles & arrows in iPhone help page about using buttons?
body: <p>Most of the apps today provides the tutorial that teaches the user to how to use the buttons in the app. This help page is normally in black color with a little alpha value (so only the background will semi-visible) with a bubble box that contains the text to define controls and the arrow which points to the corresponding component.</p>
  
  <p>Here is the sample image.. (From the app <a href="http://itunes.apple.com/in/app/mythings-for-iphone/id537678529?mt=8" rel="nofollow noreferrer">MyThings</a>) </p>
  
  <p>This is the normal page</p>
  
  <p><img src="https://i.stack.imgur.com/QmKOr.jpg" alt="enter image description here"></p>
  
  <p>And if you swipe from bottom to top, the help view will appear like..</p>
  
  <p><img src="https://i.stack.imgur.com/sEoDs.jpg" alt="enter image description here"></p>
  
  <p>Here is my doubts:</p>
  
  <ul>
  <li><p>Which one is best to create the images &amp; text in this help view? Drawing the images &amp; texts using Core Graphics or by simply putting an UIImageView with a png image? Which one is efficient?</p></li>
  <li><p>There is no problem in implementing a UIImageView with a ready-made png image. From my knowledge, the problem here is the image file size and the loading time. If we consider the drawing method, my mind things about the following problems.</p></li>
  <li><p>Drawing a rectangle is so easy. (<a href="https://stackoverflow.com/questions/7451852/how-to-draw-a-rectangle-in-objective-c">Refer here</a>). But what about drawing a rectangle with a curved corners?? Is there any function available that handle this case?</p></li>
  <li><p>Then the arrow, that points the corresponding component.. How can we find the exact point that should be pointed? (till iPhone 4S, there is no problem I hope, iPhone 5 has different height)</p></li>
  <li><p>How to draw this pointers from the particular position in the rectangle? </p></li>
  </ul>
  
  <p>Any ideas?</p>
  
  <p>Just confused!!</p>