Jellybean 4.2.1 and 4.2.2 are the same! This is an excerpt from my feature length Nexus 4 review. When the Nexus 4 gets hot, both the CPU and GPU are throttled or slowed down to prevent some kind of problem with the phone. It seems Qualcomm and Google want this in place so that the battery life isn’t incredibly short and to also to protect the battery from overheating. This may be tough on gamers because they won’t be able to enjoy the full processing power when over 36 degrees Celsius.