The best replacement for webdriver is selenium.

The best alternatives to webdriver are rated as following:
★★★★★  selenium
★★★★  rc
★★★  webdriverjs
★★★  watir
★★★  selenium rc
★★★  qtp
★★★  remote control
★★★  phantomjs
★★  remotewebdriver
★★  selenium ide
★★  webdriver backed
★★  webdriverbackedselenium
★  htmlunit
★  sahi
  selenium 2

Your alternative for webdriver is not listed? Suggest!
Speaking about webdriver, one probably shouldn't forget about phantomjs.

Other search terms related to webdriver and their ratings are:
★★★★★ phantomjs
★★★★★ testng
★ safari
selenium ide
You have in mind a companion for webdriver and it is not yet here? Propose!



Google Trends

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webdriver
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