Your iPhone will track and record places that you visit most often to provide better location-based data and suggestions across iOS11. While these suggestions can be super helpful, you may not like the idea of your iPhone and iPad tracking the locations you frequent
If you value your privacy more than you do location-based data and suggestions, you can turn the feature off.
Tap System Services. It's all the way down at the bottom of the list.
Tap Significant Locations.
Tap the Significant Locations On/Off Switch. When the switch is gray, that means the feature has been turned off.
That's all there is to it. Locations you travel to most will no longer be tracked. While this comes at the expense of not having as accurate location data in places like the Today Summary screen, it also preserves your privacy better and to a lot of us, that's more important.