The Wall Street Journal has analysed 100 applications which are quite frequently used by Facebook users. The aim was to see what content is required by the social-networking site from the user's profiles.

According to the Wall Street Journal, the analysis of 100 most popular Facebook apps showed that some look for sensitive information of users like e-mail addresses, current location and more. It will seek the content of not only the app users but also of their Facebook friends.

According to WSJ, Facebook needs apps to ask permission before accessing a user's personal information. However, the app user's friends are not intimated if their information is used by a friend's app.

The analysis of the apps activities also throws light on Facebook privacy, meaning the social-networking company is not implementing its own rules on data privacy. "We focus on helping people make informed decisions about the apps they opt for. Moreover, the app developers agree to our policies when they register. When an app is found to violate the policies of the company, we take the action," said a Facebook spokesman.

The apps are not only seeking the data directly from user's accounts, but also there are apps which are allowing unapproved advertising firms to track users. Probably, it could be violating the advertising policies of Facebook.

According to WSJ, the profiles of the users are set by default to allow the apps to obtain all data from a user's friends except religion, political views and sexual preference. Hence, even if the user's birthday and location have to be private to friends, their friends could approve an app which will obtain all the information.

According to studies, about 40 per cent did not understand when an app could be allowed to grab their personal information. Possibly, it could transfer the data out of Facebook. It also suggests that users are not able to understand the permissions list, since it can be too technical which cannot be grasped by a lay man.

In some cases, even if a user understands the permissions, they may not predict the ways their data could be used anytime in the future.