A free app for Android, by MobiSystems.

Covering many aspects of chemistry as well as other related areas, the Oxford Dictionary of Chemistry is surely an ideal reference for students and professionals alike. It offers more than 4,700 entries as well as biographical texts on key figures.

Aside from having improved and optimised app speed and user-friendly visual layout, you will also enjoy intelligent search features that will let you find target words effortlessly. You can use voice or camera search, or utilise the autocomplete and automatic spelling correction. Moreover, you may also create folders of important words and group them according to category.

The 30-day trial version offers all functionalities for free, but purchasing the premium version has additional perks, such as offline usability and quicker support for any app issues.