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.
UserGuiding - User onboarding made easy, for less. Create product walkthroughs in a couple of clicks, without breaking the bank.
Google Trends - Explore Google trending search topics with Google Trends.
Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
Keywords Everywhere - Free browser add-on for keyword volume, CPC & competition
Userlane - Digital adoption platform with interactive guidance for software applications allowing anyone to understand and master any software from the get-go.