Some rules of note in the guidelines:
User interface:
Apps that create alternate desktop/home screen environments or simulate multi-app widget experiences will be rejected
Apps that alter the functions of standard switches, such as the Volume Up/Down and Ring/Silent switches, will be rejected
Apps that look similar to apps bundled on the iPhone, including the App Store, iTunes Store, and iBookstore, will be rejected
Content:
Apps that are simply web clippings, content aggregators, or a collection of links, may be rejected
"Enemies" within the context of a game cannot solely target a specific race, culture, a real government or corporation, or any other real entity
Apps that include games of Russian roulette will be rejected
Apps that contain user generated content that is frequently pornographic (ex "Chat Roulette" apps) will be rejected
Apps containing pornographic material, defined by Webster's Dictionary as "explicit descriptions or displays of sexual organs or activities intended to stimulate erotic rather than aesthetic or emotional feelings," will be rejected
Apps that duplicate apps already in the App Store may be rejected, particularly if there are many of them
Apps that are not very useful or do not provide any lasting entertainment value may be rejected
Apps may contain or quote religious text provided the quotes or translations are accurate and not misleading. Commentary should be educational or informative rather than inflammatory
Apps that misspell Apple product names in their app name (i.e., GPS for Iphone, iTunz) will be rejected
Bandwidth:
Audio streaming content over a cellular network may not use more than 5MB over 5 minutes
Video streaming content over a cellular network longer than 10 minutes must use HTTP Live Streaming and include a baseline 64 kbps audio-only HTTP Live stream
Apps that excessively use the network capacity or bandwidth of the APN service or unduly burden a device with Push Notifications will be rejected
Privacy:
Apps that do not notify and obtain user consent before collecting, transmitting, or using location data will be rejected
Apps cannot transmit data about a user without obtaining the user's prior permission and providing the user with access to information about how and where the data will be used
Apps that require users to share personal information, such as email address and date of birth, in order to function will be rejected
Apps that target minors for data collection will be rejected
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