Can I use an Iphone 5s with out a plan?

With no plan no at&t verizion t-mobile and sprint just the iphone

Yes and no. There are apps you can download when connected to Wi-Fi such as TalkaTone and TextMe that allow you to make calls and send texts. However, you must have a connection to Wi-Fi to do so. I have not personally used TextMe yet, but I know with TalkaTone you don't have a set number for receiving calls.

Yes.

Unless you want to use an iPhone.

Then no.

Yes you can use it just like an ipod touch, but in that case why net get the ipod touch instead