Sales by outside merchants on Amazon.com Inc.’s Marketplace were up 27% in April 2014 compared to April 2013, according to ChannelAdvisor. The company produces monthly reports that compare its clients’ sales on various online marketplaces and channels, including Amazon.com, eBay Inc., Google Search and Google Shopping.

The announcement of Amazon Fire TV on April 2 might have boosted e-commerce sales on the marketplace, Scot Wingo, ChannelAdvisor’s CEO, says in a blog about the April results. “These launches usually ‘spill over’ into increased e-commerce sales,” Wingo says.

Client retailers selling on Amazon had the greatest increase in sales among the channels tracked, while clients on eBay had an increase of 14% in April compared to April 2013. Wingo points out that those rates are still higher than the e-commerce baseline growth rate of 13.1%, according to comScore data..

A deeper dive into the eBay numbers reveals that retailers selling fixed-price goods on eBay increased revenue by 18.1% in April compared to a year earlier. The big decline continues to be in auction-format sales, were down 14.5% over the previous year.

Google generated slower growth than Amazon and eBay for ChannelAdvisor clients. Revenue from paid search ads on Google Search grew only 4.3% in April compared to an 11.2% year-over-year growth rate in March. Year-over-year growth on Google Product Listing Ads was 7.8% compared to the previous year.

Conversion rates on Google Product Listing Ads increased 7.9% in April compared to the previous year, but customers spent on average 11.1% less in April 2014 than April 2013—down to $99.21 from $111.58.  Conversion rates for paid search ads on Google were up 1% in April 2014 compared to the previous year. Customers spent in April an average of $121.04—the same as April 2013.