If a list item with no content is encountered like
* some entry * * another entry
that will produce HTML code like
<li>some entry</li> <li class="mw-empty-elt"></li> <li>another entry</li>
On HTML browser skins there is a display:none rule for .mw-empty-elt which will hide that empty item.
For Mobile App this rule is missing, and the empty item is shown.