Navigate to your home screen and open the Settings app. The Settings app is where we can easily find the Safari settings. The Settings app is often found in the utilities folder.
You'll have to scroll down quite a bit, but once you have found Safari, give it a click. This is where all your Safari settings can be located.
In Safari settings, you are going to see tons of options. Scroll down until you see "clear history and website data" in blue lettering and give it a click.
To ensure that you are sure about clearing this data, your iPhone will let you know what is being removed and you will have to click "clear history and data" in red lettering to confirm. Once the data is cleared, the once blue lettering will be a dim gray.
As the notification states, clearing history and website data will clear history, cookies, and other data (mostly cache). If Safari is syncing to iCloud, then this will be cleared from all the devices sharing the same Apple ID.
Some apps, though they are few and far between, include a reset or clear cache option. For example, Slack has a "reset cache on next launch" option, so that cache will be reset upon launching the app next.
To clear third-party app cache try the following:
- Open the Settings app.
- Scroll down toward the bottom of the page and click a third-party app.
- See if it has a similar option for clearing cache.
- Continue through the list of third-party apps to clear their cache.
Unfortunately, most apps do not have this option. It is rare. You can, if you want, also delete unwanted apps to clear their cache. Only consider deleting apps you do not want since this deletes all app data.
Sometimes, when you are busy or out and about and your iPhone starts ringing, you don't want to pick it up, but you know it might be so-and-so with that important call you've been waiting on.