I think this email also makes quite a brilliant use of responsive design. The colors are bright, and it's not too hard to scroll and click -- notice the CTAs are large enough for me to hit with my thumbs. Also, the mobile email actually has features that make sense for recipients who are on their mobile device. Check out the CTA at the bottom of the email, for example: The "Open Stitcher Radio" button prompts the app to open on your phone.
Frequency matters, and how often you send emails can have a significant impact on your revenue and email engagement (and unsubscribe) rates. Send too much and subscribers can suffer email fatigue causing them to disengage and unsubscribe. Send too few and you lose the attention of your audience. They may even forget why they signed up leading them to unsubscribe. 

The connection between television appearances and new subscribers is historically difficult to track, but WP Curve’s television appearance significantly increased search traffic for branded terms – and search traffic accounts for 42% of WP Curve’s new signups. With TV as their megaphone, WP Curve saw a 27% increase in recurring revenue for in March. Read all about it here. https://campaignonthecloud.com/wp-content/uploads/2016/05/email_market_image.png

Recently,[when?] there has been a rapid increase in online lead generation: banner and direct response advertising that works off a CPL pricing model. In a pay-per-acquisition (PPA) pricing model, advertisers pay only for qualified leads resulting from those actions, irrespective of the clicks or impressions that went into generating the lead. PPA advertising is playing an active role in online lead generation.
Set up marketing automation workflows to categorize leads and segment them into lists using criteria established in Step #1. Use these lists to nurture leads with relevant content and personalized email communications. Also use them for targeted campaigns, segmenting leads with a certain role or title or within a certain industry or market segment. https://subiz.com/blog/wp-content/uploads/2015/06/email-marketing-campaign.jpg
Online surveys: Consumers are asked to complete a survey, including their demographic information and product and lifestyle interests. This information is used as a sales lead for advertisers, who purchase the consumer's information if provided. The consumer may 'opt-in' to receive correspondence from the advertiser and is therefore considered a qualified lead. 
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