The best replacement for add ons is plugins.

The best alternatives to add ons are rated as following:
★★★★★  plugins
★★★  add-ons
★★  plug ins

Your alternative for add ons is not listed? Suggest!
Speaking about add ons, one probably shouldn't forget about internet explorer.

Other search terms related to add ons and their ratings are:
★★★★★ internet explorer
★★ mozilla firefox
★ internet explorer 7
★ ie8
You have in mind a companion for add ons and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of add ons in all years. Click on graph for more.
add ons
plugins
add-ons