Comprehensive 2015 article published in Springer’s Journal of Computer-Aided Molecular Design. Here is the abstract,
The IUPAC International Chemical Identifier (InChI) is a non-proprietary, international standard to represent chemical structures. It was conceived 15 years ago, and has been is use for 10 years. The InChI Trust is developing and improving on the current standard, further enabling the interlinking of chemical structures on the web. This mini-review looks at the widespread adoption of InChI in software and databases.