Sailthru

This plugin provides fast and easy integration of the core Sailthru features into your WordPress site.

Sailthru for WordPress

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Unless is a UX optimization engine. It lets you segment website visitors into audiences, show tailored versions of your web pages to each of those audiences (content, add-on components or inline features), and subsequently measure success rates using AB tests. This typically will increase your websites conversion rates and ad revenue.
This plugin adds the Unless service to all your WordPress pages. Simply copy/paste the Account ID from your <a href="https://unless.com/" rel="nofollow ugc">Unless dashboard</a> into the input field and save settings.
Important note: this version of the plug-in works from version 5 of Unless. If you are still on version 4, go to Unless.com to upgrade. You will be rewarded with many additional features and an even faster service.

Unless

Install the Unless user experience optimization service on your website. You can insert targeted, personalized content and features, and automatically …

Sailthru for WordPress vs Unless