I have posted this before . but its relevant Product Reviews free MailChimp integration free to $ 9 a month requires a mailchimp account which I believe has a free tier this one is worth a lot if you want to remarket . or heck to even send targeted emails out when a customer buys a specific product or category of products . Its very slick and using MailChimp and this app allowed me to drop about $ 50 a month in other apps that were doing remarketing for us . Subuno $ 19 . 00 a month . Our volume is low enough that we are on that tier , but worth it at many times that price Product Upsell Bold apps is $ 9 . 99 to $ 59 . 99 a month , based on volume of upsell views Product Discount Bold apps one time $ 99 . 99 , and again more than worth it . The Motivator Bold apps $ 4 . 99 to $ 9 . 99 depending on feature set you want to use Exit Offers $ 9 . 99 Vantage Analytics Free for stats , management fee if you use them for ads Persistent Cart The one by MaxEffi Basic functionality free , $ 9 a month if you want some of the extra featuresWe also run a few proprietary apps that I wrote to help us with our business model , etc . including a postal address verifier that will clean up their shipping address using USPS services . One of these days when I get the time I will see about opening that one up to others . One thing to note , I periodically every 23 months go through and review our apps and see how they are working and decide if they are paying for themselves . any that don ' t pay their own way get removed . so our list is slowly evolving as we make things more profitable for us .