ひらがなツールチップ is a free Chrome browser add-on developed by NOZAPP（ノザップ）. This add-on allows users to display hiragana tooltips when hovering over kanji characters. With a simple click on the icon, users can easily toggle the feature on or off. It is recommended to keep the add-on turned off when not in use.

The main feature of ひらがなツールチップ is its ability to provide hiragana readings for kanji characters. This can be particularly useful for learners of the Japanese language or individuals who encounter kanji characters frequently while browsing the web. By simply hovering over a kanji character, users can instantly see the corresponding hiragana reading in a tooltip.

Overall, ひらがなツールチップ is a handy tool for Chrome users who want to easily access hiragana readings for kanji characters. Its simple interface and toggle feature make it convenient to use without being intrusive during regular browsing activities.