Remember the days when it wasn’t uncommon to read an article speculating about whether or not social media would kill email? In fact, if you count the increasingly popular business communication tool Slack, it’s still a subject that comes up.

These days, however, it seems like largely social-oriented services are utilizing email more than ever.

A couple weeks ago, stories circulated about new email effort from Instagram. It has a new email digest called “Highlights” that displays several posts from people the user follows in an attempt to drive some more engagement.

“Some people will surely bristle at the idea of receiving more email, especially one’s they didn’t explicitly sign up for,” wrote TechCrunch’s Josh Constine. “However, Highlights could solve an issue common amongst maturing social networks that show a live, reverse chronological feed of posts. It impacts networks like Instagram and Twitter, but not relevancy-sorted streams like Facebook’s.”

He did note, however, that even Facebook has tested various re-engagement tools including email.

Twitter has sent users emails about activity from their networks for a long time, and this is only one of many email options users can choose whether or not they wish to receive.

Even reddit recently launched a weekly email newsletter aimed at showcasing some of its top content to more casual users. On Product Hunt, Product manager Heath Black said this about reddit’s reasoning for getting into email after all these years:

First of all, we know that a lot of people interact with reddit content across the web on a daily basis. They love the content, but don’t necessarily understand that concept of reddit itself. This helps us build some context for those two things for new users, reddit lurkers, and folks that just can’t spend all day on the site.

Secondly, as the site continues to grow, and the amount of content submitted grows with it, finding good content can be incredibly difficult. Discovery is a hard problem to solve, and much of the best content can be found in some of the smallest corners of reddit. A weekly digest gives us the ability to call out those good content creators, no matter where they reside on reddit.

Third, since reddit content blows up pretty often, we want to make sure that the creators of that content are given the credit they deserve. Many publishers that use their content don’t credit at all and it absolutely pisses our users off. We want reddit users to know that we love them and the creative things they do.

StumbleUpon has also been using email to drive engagement. Earlier this year, we had a chat with Director of Marketing Anne Gherini to learn more about its strategy. She talked about running tests to gauge what content its users want to see and how its emails feature dynamic content generated by its personalization algorithm.

“StumbeUpon is in essence an entertainment company. What we are finding is that entertainment is judged by emotion and that emotion can sometimes be better determined by a human over just an algorithm,” she told us at the time. “Our approach to CRM is simple. It is a privilege to be able to be in a user’s inbox or to pop up on their newsfeed. We don’t take this privilege lightly, so we are dedicated to delivering the right mix of content to the right users at the right time. Finding this balance involves in-depth testing and proper data-mining. Segmentation, personalization and a fantastic CRM team are making this happen at SU. We are already seeing the results and there are many more changes and improvements in the pipeline.”

“The weekly recommendation emails have had the highest engagement and our continuous optimization of these emails has enabled us to keep increasing our KPIs,” she said, adding that they were still looking at building out additional email programs based on users’ usage patterns.

In the days when the desktop ruled, email overload was a legitimate concern. Nobody enjoys sitting down at their desk and sorting through an inbox full of messages, but the rise of the smartphone has changed our email habits. It’s basically just another notification you get throughout the day, which you can easily swipe away for later, delete, or open and engage with at your leisure. This is likely why email is such an attractive way for social networks to re-engage users.

Maybe you don’t have time to scroll through reddit, but you might want to take a quick glance at some top stories. Maybe you it’s been a while since you fired up the StumbleUpon app and thumbed through a bunch of pages from around the web, but if you see some interesting stuff from categories that you’re specifically into, pushed right to your inbox, well, maybe you won’t mind pausing to take a look.

According to Experian’s Q1 Email Benchmark report, 51% of total opens occurred on a mobile phone or tablet during the quarter. The majority of email opens ocurred on mobile phones or tablets for all industies except publishers and business products and services. The majority of total clicks occurred on mobile phones or tablets for media and entertainment (56%) and multi-channel retailers (51%).

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