Mobile devices often have limited available wireless bandwidth, as well as limited storage space both in active memory and device storage. A large portion of data stored in these locations can be classified as textual, such as emails, contact and calendar information, documents, etc. The vast majority of the words used in these textual data examples are known words from a relatively small vocabulary for each language. This paper analyses the use of using word indexing as a means of reducing storage requirements while not requiring any decompression time. Experiments show significant reductions in storage requirements compared to plain text, and similar storage requirements of existing compression algorithms.