There are unfortunately a lot of applications for mobile devices which do a lot more than is written on their 'features' page. You might have noticed on Android devices, you are shown a list of the permissions that the app is asking for when installing. On iPhone, permission is sought when the app first asks for use of a certain function. You might also have asked yourself why an application is getting permissions to your location, contacts, emails, SMS / MMS etc.
Some mobile applications have been designed to specifically gather user data to then sell on to third parties. This is a major problem and an obvious invasion of privacy. Companies often provide apps to access their services even when their standard web site is perfectly satisfactory. They do this in the main because putting an app on your device bypasses the majority of privacy controls placed on them by your web browser. If you are happy with a company's web site, then don't install their app.
If you have not already done so, check the permissions that have been given to applications on your telephone / tablet.
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