If your iPhone 6, 6+, 6s, or 6s+ is working slow then try this simple tweak to speed it right up.
Simply follow the directions:
Step One:
Tap on Settings
Step Two:
Tap on General
Step Three:
Tap on Accessibilty
Step Four:
Tap on Increase Contrast
Step Five:
Turn on Reduce Transparency
And that’s it! Your iPhone should now be working much faster.