Nextag ROI Optimizer
3 websites

Nextag ROI Optimizer is free to use

http://nextagsellers.blogspot.com/2010/02/roi-optimizer.html

2 Feb 2010 ... The ROI Optimizer is one of the most important features that you can implement to understand the performance of your account. What is it?

VS

Tell-a-Friend
275 websites

Tell-a-Friend is free to use

http://tellafriend.socialtwist.com/

SocialTwist is a customer acquisition and retention platform that generates viral referrals for businesses, using the social connections of their customers.

Market Share by Top Websites

1 Tell-a-Friend is leading in Top 100K Sites and Top 1M Sites.

2 In terms of market share, Nextag ROI Optimizer is clearly lagging behind, losing to Tell-a-Friend in all segments.

Websites Categories

1 Tell-a-Friend has better usage coverage in more websites categories. Including Science & Education, Arts & Entertainment, Community & Society, Computers Electronics & Technology and 16 other categories.

2 Nextag ROI Optimizer hasn't got a lead over Tell-a-Friend in any websites category.

Geography

1 Tell-a-Friend is leading in most countries, including United States, India, United Kingdom, Canada and 43 other countries.

2 Nextag ROI Optimizer hasn't got a lead over Tell-a-Friend in any country.