This paper describes a study for assessing how many free Android games with in-app purchases were susceptible to data manipulation via the backup utility. To perform this study, a data set with more than 800 games available in the Google Play store was defined. The backup utility, provided by the Android Operating System (OS), was used to backup the app files into a Personal Computer (PC) in order to find and manipulate sensitive data. In the cases where sensitive data was found, the applications were restored and the games tested to assess if the manipulation was successful and if it could be used to the benefit of the user. The results included show that a significant percentage of the analyzed games save the user and app information in plaintext and do not include mechanisms to detect or prevent data from being modified.