ChemKosh

This app is like Dictionary app but for chemistry. It has a lot of chemical compounds both from organic and inorganic.
First you will type the name of compound and search it by clicking on search icon or by clicking enter in keyboard. After, it will show data for that compound. It shows information of compound like its molecular formula, Molecular Weight, Hydrogen bond donor, Hydrogen bond acceptor, Its IUPAC name, Number of non hydrogen elements, number of isotope atoms and rotatable bonds. It also shows the image structure of the given input compound.
This app becomes very useful for study purpose also, as it can give enough information of given compound so that one can get great marks in exam!!!
The whole app is open source at GitHub under username hemish11 and named as chemkosh.