manuelmasia

Here is the demo page: <a href="http://www.pixedelic.com/plugins/pixgridder" title="PixGridder" rel="nofollow ugc">PixGridder</a> where a link to Pro version is available (pixgridder-pro)
I prefer to define this plugin as a “grid builder” instead of a page builder, because a page builder is commonly intended as a tool that allows to create sections and, usually, comes with shortcodes such as tabs, accordions, particular sections, galleries etc… And, in many cases, all these shortcodes are not compatible with other similar plugins you could prefer to use.
PixGridder is instead very simple, because it only allows to split your page into rows and columns by moving the functions available on your tinyMCE editor from the whole page to each column you decide to split your page into. In this way you can use the plugins you prefer with the shortcodes you prefer (and also the buttons available on your tinyMCE editor) since the editor is exactly the same one you would have without using PixGridder.
<h4>How it works</h4>
PixGridder doesn’t generate shortcodes, it only puts into your posts and pages some html comments like this: <code></code>
They’re invisible except through the source code. So if you want to disable the plugin you don’t have to worry about a lot of strange and unuseful shortcodes across your content because everything will be hidden for both the users and the search engine robots.
However, if you want to remove any trace of the plugin from the source code of a page, you can do it by enabling the “no trace” option: you’ll get rid of all the HTML comments, but you’ll keep unaltered your content.
<h4>Page builder visual description</h4>
Take a look to the <a href="https://s.w.org/plugins/pixgridder/screenshot-2.jpg" rel="nofollow ugc">2nd screenshot</a>
<ol>
<li>title and version of the installed plugin</li>
<li>Preview tab: by clicking it you will see the live site with a preview of the changes, not editable from the preview visual itself</li>
<li>Builder tab: where you can edit your page/post by using the grid builder</li>
<li>row dragger: use it to sort your rows and move them to the top or to the bottom</li>
<li>ID and class: use it to open a dialog box where to add an ID or a class to your row</li>
<li>clone button: clone your entire row and append the clone below the original one (everything will be cloned, cloumns, IDs, classes etc.)</li>
<li>column select: select how many columns your row is based on</li>
<li>delete: remove the row</li>
<li>alert icon: this icon will appear when you make a not-allowed operation, such as adding a column where there is no space for other columns or try to reduce the width of column if it already has got the minimum width allowed</li>
<li>add row: click to add an empty row</li>
<li>add column: click to add an empty column</li>
<li>column dragger: use it to sort your columns and move them to the left or to the right inside a row</li>
<li>column content: here is displayed a preview of the content (the font and the text color won’t reflect on the frontend)</li>
<li>expand column: click to increase the width of the column</li>
<li>contract column: click to reduce the width of the column</li>
<li>edit column: click to open a dialog box where to edit the content of the column (a tinyMCE editor will open in the dialog box, the width of the textarea will be relative to the max width set for the theme you’re using and the width of the column you’re editing)</li>
<li>clone button: clone your entire column and append the clone to the right of the original one, if there is enough space (everything will be cloned, content, ID, class etc.)</li>
<li>ID and class: use it to open a dialog box where to add an ID or a class to your column</li>
<li>delete: remove the column</li>
<li>“Disable the grid builder”: tick the checkbox and update the page → now the page is editable without using the grid builder, but the frontend still displays columns and rows, so pay attention to not remove any html comment or you risk to break the layout</li>
<li>“Remove any trace of PixGridder from this page”: tick the checkbox and update the page → all the row and the columns will be removed but without touching the content, still available both on the frontend and on the editor</li>
</ol>

PixGridder

A simple page grid composer that splits your pages into ordered grids, a builder for rows and columns

johannesfosseus

This is a small but great plugin that makes it possible to add drop zones to your frontend. It uses HTML5 native drag/drop javascript methods so use a modern browser!
Options 
You can choose if you want to use excepts, and images, and the image max heigth and width

Drop-Zone

Adds a widget that adds "drop zones" to your site front end. Then you can drop posts to the zones and they will stay, magic!

PixGridder vs Drop-Zone