With a quad-core 1.9GHz processor, the Samsung Galaxy S4 is one of the fastest phones on the planet, but sometimes it can be hard to tell. Samsung's Touchwiz UI is bursting at the seams with software goodies, but these can have an impact on how the system feels when you use it.
This tip comes from the good folks over at the XDA Developer's forum, and you'll be surprised at the difference when you are finished.
First, you need to go to Settings > More Tab > Developer options.
If you can't find the 'Developer options' menu option, you'll need to go first into 'About device', scroll down to the bottom and tap on 'Build number' 7 times. As you start tapping you should see a countdown appear, then a message about Developer options when you have finished.
In Developer options, go down until you find Window animation scale, Transition animation scale and Animator duration scale. Turn all of these option to 'Off'. Now, check to see how much faster it feels to use the phone, especially turning on from standby and switching between screens.
The three options switched off are part of the TouchWiz UI and control animation elements for when you are moving between sections of the phone. Samsung think these elements give the phone a polished feel, and you might agree, but we think it just slows things down. If you don't like the effect of having them off, you can easily reserve the steps above.