Is it true that an Iphone is pretty much useless without other apple products?

Is it true that an Iphone is pretty much useless without other apple products?

I use iphone and windows desktop.

No, apple is fine with anything! Haha I have a dell computer and everything works just like any apple product would!

Hell no. I have an iPod and it's great even all by itself (and some of my family members decided to get iPhones). You can do fine with any apple product that works (as long as it's part of the main branch of devices Apple supports). Hope this helped.

Absolutely not. You can use the iPhone with Windows which is not Apple.

I don't think that it's useless because you can sync it with any computer and not just with Apple computers. It can pretty much handle itself if you just know the proper way of using it.
Gadgets usually have problems when users try to experiment with it.