stigcq

A plugin offering a widget showing recent photos in posts. It can be configured 
as for how many photos to show, the title on the widget and max width and height for 
thumbnails.
The thumbnails links to the post where the photo is showing. They show a mouse over 
effect with bigger version of the photo in a tooptip.
It has option to exclude photos from the view.
It has only been tested with WP 4.2, it might work with lower versions.

Recent photos widget

A simple widget which shows thumbnails of latest photos in posts

snapwidget

SnapWidget Social Photo Feed Widget is an easy way to embed your Instagram photos and videos on your website or blog to display your photos. The widget offers the same functionality and customization available for widgets embedded from <a href="https://snapwidget.com" title="Instagram widget" rel="nofollow ugc">SnapWidget</a>. Supports the Instagram Basic Display and Graph API’s.
Features
<ul>
<li>Simple and easy to use</li>
<li>Multiple layout options (Grid, Board, Scrolling, Slideshow and Map)</li>
<li>Secure, supports HTTPS websites</li>
<li>Refreshes with new photos every 15 minutes (5 minutes for Pro widgets)</li>
</ul>
Pro Features
<ul>
<li>Hashtag Widgets</li>
<li>Widget Analytics</li>
<li>Shoppable features</li>
<li>Add your own custom CSS</li>
<li>Display photos in a lightbox</li>
<li>Previous / Next buttons to display older content</li>
<li>Creating widgets for other users</li>
</ul>

SnapWidget Social Photo Feed Widget

The widget requires connection to an external (non-instagram) site in order to simply display the Instagram photos.

Poor

SnapWidget Social Photo Feed Widget is an easy way to embed your Instagram photos and videos on your website or blog to display your photos.

Recent photos widget vs SnapWidget Social Photo Feed Widget