A while back we posted a guide on How to get flash on the iPad and iPhone 4, while the guide was very helpful it did look like a rather daunting task, however thanks to Cydia repository Benm.at, the whole process just became much easier. If you want to install Frash on your jailbroken iOS device, it’s now as simple as following these steps:
1. Open Cydia > Manage > Sources
2. Edit source and add http://repo.benm.at
3. Search Frash and install it.
If you did this correctly then you should have flash running on your device.
[Guide taken from Gizmodo.com]