Install Flash (aka Frash) to iPad is possible as long your iPad is jailbroken, now installing the same is available too for iPhone 4. And RedmondPie has compiled the how-to guide plus he also added a video guide in case you prefer an audio tutorial, so if you are interested to take risk on this educational and testing purpose only prepare yourself.
But be sure you are fully aware of or else back away, because you might be risking your iPhone’s performance.
Here’s the RedMondPie link to: how to install Flash (Frash) on iPhone 4
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