On desktop, the content div specifies the text direction based on the content language:
<div id="mw-content-text" class="mw-content-ltr" lang="en" dir="ltr">
On mobile, we don't:
<div id="content" class="content">
The first step to fixing this is to add dir="xxx" to the content div. That will fix the text alignment and punctuation. We may also want to change how we handle aligning images and TOC to match desktop as well (but see Bug 62349).