Emails with six to 10 words in their subject lines have the highest open rates, according to Retention Science. The company analyzed one billion emails and found that these messages see on average a 21 percent open rate. Emails with subject lines in the 11 to 15 word range had a 14 percent open rate and emails with up to five words in their subject line had on average a 16 percent open rate.

InterFAX allows consumers to use email in order to send a fax. Users must simply sign up for the service and then send a fax as an email by adding [country code][area code][fax number]@fax.tc to the "to" filed of their email. The service charges by the page, beginning at $10.

India's Income Tax department has issued a warning telling taxpayers to beware of emails claiming to come from its agency. Spammers have been trying to dupe citizens into sharing personal data via malicious emails. "Taxpayers are requested not to respond to any email or any type of communication sent to them requesting them to furnish their personal particulars such as bank account details, passwords, one-time password etc purported to be from the Income Tax department," the advisory said.

Julian Assange has defended WikiLeaks for publishing the personal emails of CIA Director John Brennan. Speaking online from the Ecuadorian Embassy in London, Assange claims that by publishing the email records he served the public. The revelations exposed Brennan's donations to Obama's 2008 campaign and Brennan's bids to win government contracts when he was working in the private sector. The CIA has condemned WikiLeaks for publishing the stolen emails.

The State Department has released new details about Hillary Clinton's private email server. One of the latest details reveals that actor Ben Affleck had her private email address while she was Secretary of State. The Hollywood star emailed Clinton about an initiative he was working on to reform security in the Democratic Republic of the Congo.

Slack, an app that is hoping to cut down on work email, claims that its tool is working. According to a new survey from the company Slack users see an average of 48.6 percent reduction in email and almost 80 percent of these users claim that the app has improved transparency and office culture. The company, which is currently valued at a $2.8 billion valuation, raised about $340 million in less than two years.

AOL has released a new email app for Android devices that is reminiscent of Google's Inbox app. The app is called Alto and supports AOL, Gmail, Outlook, Yahoo and iCloud email clients among others. The app also allows users to quickly sort through stacks of attachments and images in their inbox in order to find documents quickly.

Republican presidential candidate Jeb Bush has released a collection of emails from when he was governor of Florida in an e-book called, "Reply All." The book includes 730 digital pages of emails sent to and from constituents, journalists and others while he held office. The book comes as the candidate kicks off his official "Jeb Can Fix It" tour.