How to find the iOS or macOS Version
On an iPhone or iPad
To find the software version installed on your device, go to Settings > General, then tap About.
Which macOS version is installed?
From the Apple menu 
in the corner of your screen, choose About This Mac. You'll see the macOS name, such as macOS Mojave, followed by its version number. If some product or feature requires you to know the build number as well, click the version number to see it.
This example shows macOS Catalina version 10.15 build 19A583.
How to delete cookies/cache on an iPad or iPhone
Safari: Delete history, cache, and cookies
Here's how to clear information from your device:
- To clear your history and cookies, go to Settings > Safari, and tap Clear History and Website Data. Clearing your history, cookies, and browsing data from Safari won't change your AutoFill information.
- To clear your cookies and keep your history, go to Settings > Safari > Advanced > Website Data, then tap Remove All Website Data.
Chrome: Clear all cookies
If you remove cookies, you'll be signed out of websites and your saved preferences could be deleted.
- On your iPhone or iPad, open the Chrome app
. - At the bottom right, tap More
, then Settings 
. - Tap Privacy, then Clear Browsing Data.
- Check Cookies, Site Data. Uncheck the other items.
- Tap Clear Browsing Data, then Clear Browsing Data.
- Tap Done.