At any given time you can reset your Nexus 4 smartphone to the factory default settings, meaning you will bring your phone back to the same state as it was on a day when you took it out of the box.
If you are accessing certain websites very often with your Android powered Samsung Galaxy S2, I suggest you to add a bookmark shortcut to your phones Home screen.
Nexus 4 smartphone comes with a bunch of Android widgets you can add to one of the screens. Let me show you how to add a widget to a screen and how to customize it.
If for some reason your Android powered smartphone does not perform as good as it used to, or you want to sell it I suggest you to bring it to its original factory state.
Bookmarks are a great way to save the website addresses you don't want to forget about, this is how you add them to a stock web browser on your Samsung Galaxy S2.
A really useful feature in case you want to receive a warning notification before you use all of the mobile data available according to your mobile provider contract. It's a great way to avoid additional charges.
If your phone doesn't want to boot up again after the update, it gets stuck in a black screen, follow this tutorial where we root the Galaxy SII with Odin and put an official Samsung Android 4 ICS on it.