I was snooping around in the directory of an official AppStore app which should remain unnamed and discovered several .txt files I took a look at out of curiosity. To my surprise the headers of these files stated that these files belong to a well established open source library and development toolkit which is disributed under the GPL v2. After I checked the capabilities of this open source library in more detail it became clear that 80-90% of the app relies on this library to do its work. Thus under the terms of the GPL v2, by including this open source library the app also is required to be published under the GPL v2 or later. However, I have found no statement in app itself or on the official homepage about this. This only leaves the conclusion that this app is not open-source and that the authors of that app try to make a buck out of the hard work of the open source community. Of course, I have informed the copyright holder of the open source library about this infraction and although I have not received an answer I assume that legal actions will be taken. This whole thing leads to the question how well Apple actually checks the apps they accept for sale on the AppStore. I made my discovery simply by taking a look at the .txt files in the directory and the header of these files clearly gave them away as open source software. So one can only assume that Apple not even did this really simply check which raises the question if Apple checks the software at all. Since both iPhone and iPod are devices with an internet connection which may store large amounts of personal information and the user (on a not jailbroken iPod) has no way to restrict the access of apps to the internet by closing ports and so on, I always assumed that Apple would check each app for security risks. In the lights of the things above however, it seems that the apps are not checked at all and could be full of trojans and spyware without anyone noticing. Thus it seems if you are really worried about security issues the only way to go is to jailbreak your ipod and only use open-source apps or if you really need AppStore apps find a way to restrict the access of these programs to the internet.