Madgicx - Ad performance beyond human limits
KeywordTool.io - KeywordTool.io is the best FREE alternative to Google Keyword Planner and Ubersuggest. It uses Google's autocomplete feature to get over 750+ long-tail keywords for any given query.
Facebook Ad Hunter - Facebook Ad Hunter uncovers hidden audiences to target when running Facebook Ads.
Google Trends - Explore Google trending search topics with Google Trends.
AdEspresso - Optimize your Facebook Ads Easily, Like Morning Coffee
Keywords Everywhere - Free browser add-on for keyword volume, CPC & competition