Menu showing dfferently on ipad and iphone

For which theme?

It’s called media maven

You can see here https://www.casalinghidisperati.com

Looking at the demo website, it seems that theme intentionally made the symptoms you’re experiencing for iPad and iPhone.

So, there is nothing i ca do?

You can override them by writing your own media queries rules for particular browser sizes <- You’ll need moderate CSS knowledge.

Installing a plugin for ipad and iphone view is not possible? Woult id solve the problem?

Which plugin?

I am not sure… I just dont want to change the theme…

I’m sorry but your chosen theme is not released under GPL. Non GPL products are not welcome in the WordPress community. Official WordPress policy states that all plugins and themes that are publicly released are required to adhere to https://www.ads-software.com/about/gpl/

Also, given this particular theme provider, I would strongly recommend that you read this article and consider changing to a theme from a reputable source asap.