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<table border="1" cellspacing="0" cellpadding="4">
  <caption>Comparison of models</caption>
  <tr>
    <th>Model</th>
    <th>OS</th>
    <th>Display</th>
    <th>RAM</th>
  </tr>
  <tr>
    <th>Samsung Galaxy S7</th>
    <td rowspan="2">Android</td>
    <td>5.1"</td>
    <td>4 GB</td>
  </tr>
  <tr>
    <th>Sony Xperia Z5</th>
    <td>4.6"</td>
    <td rowspan="2">2 GB</td>
  </tr>
  <tr>
    <th>Apple iPhone 6s</th>
    <td>iOS</td>
    <td>4.7"</td>
  </tr>
</table>