Requires iOS 6, tall screen device
Force legacy apps to launch in full screen on iPhone 5. (note: this tweak simply forces SpringBoard to treat every app as if it supports tall screen. This may cause some apps to crash or behave strangely. If you need a more sophisiticated per-app switch, check out tweaks such as FullForce for Phone).
An SBSettings toggle is also available.
Open source on Github
No options to configure.