Asvin Balloo

This plugin will add a “Back to top” icon automatically to your blog. It features a smooth scrolling effect and customizable options such as the color, position and scroll duration, sprinkled with some cool CSS3 effect.
By <a href="http://htmlblog.net/" rel="nofollow ugc">Asvin Balloo</a>.
Supported features:
<ul>
<li>Smooth scrolling animation</li>
<li>Customizable options via the admin panel</li>
<li>Works on almost all browsers</li>
<li>No need to add any markup to your theme</li>
</ul>

WP To Top

This plugin will add a "back to top/ scroll to top" icon automatically to your blog.

vurghusm

isiaToTop plugin is based on the isiaToTop js plugin available at: 
<a href="https://github.com/vurghus-minar/isiaToTop" rel="nofollow ugc">https://github.com/vurghus-minar/isiaToTop</a>
You can check out the Codepen demo here: 
<a href="https://codepen.io/vurghusm/pen/NZqGxb" rel="nofollow ugc">https://codepen.io/vurghusm/pen/NZqGxb</a>
It is mobile friendly and fully customizable.
Contribution, feedback, issue reporting, and comments are welcomed via the github.
<h3>Overriding defaults css and js</h3>
<ol>
<li>To override the <code>css</code> and <code>js</code> files, create a <code>config-isiatotop</code> folder in your theme or child theme.</li>
<li>
Copy the <code>css</code> and <code>js</code> folders located in the <code>isiatotop/assets/public</code> directory to the <code>config-isiatotop</code> and override files there.
The directory structure should look like this. 
–themes 
—->your_theme or child_theme 
——>config-isiatotop 
——–>css 
———->custom.css 
——–>js 
———->init.js
</li>
</ol>

isiaToTop

A versatile and mobile friendly 'scroll to top' plugin based on isiaToTop.

WP To Top vs isiaToTop