Layout by Instagram - Combine multiple photos into a single image
VWO - Use VWO to tweak, optimize & personalize your website with minimal IT help.
Likecreeper - Randomly hit like on a friend's horrifyingly old Instagram
Optimizely - A/B testing you'll actually use.
Top Nine 2017 - Creates a collage of your top 9 Instagram posts for 2017
Crazy Egg - Through Crazy Egg's heat map and scroll map reports you can get an understanding of how your visitors engage with your website so you can boost your conversion rates.