The tweaks are available within the settings of all recent Android phones in a section called “Developer options.”
This section might be hidden on some phones, but it’s very easy to access. On many phones, you just have to open a certain page in the settings and tap a button seven times. Use Google to figure out how to enable Developer options on your phone if it’s currently hidden (for example, search “enable developer options HTC One”).
Once you have access to Developer options, simply scroll until you find the following three settings, which may be located on the main screen or within an “Advanced” subsection:
Window animation scale
Transition animation scale
Animator animation scale
Tapping each of the three aforementioned settings will reveal that it’s set to “1x” by default. If you want to speed up your phone or tablet dramatically, simply change each of those three settings to “.5x” — that’s it. p.s restart your device.