Image menu on responsive WordPress

Question

1) Why WordPress only use based on "text" menus (navigation) only?
Maybe the answer is "it is for SEO and mobile responsive WordPress".
Am I correct? any other opinions?

2) What if I create "image navigation menu" for only PC version and create "mobile navigation and responsive" maybe select box.
Is it possible?

I have found is_mobil() and I think it can be done.

Please see this link http:www.tourtips.com/ and see the beautiful image navigation menu. I really want to use it but I worry about mobile version.
Is there any way to keep this image menu for PC version and create another mobile or small size menu for smaller devices? if it's possible, what codes I should use?

I think some of codes should be loaded depends on devices such as: if...is_mobile()... and CSS parts... and loading scripts...

Any more things I should worry? any tips? any tutorial links?