Will there be an iPhone 6 and so on?

I heard a rumor that Apple was thinking of making one last iPhone (5S) then ending the line of iPhones to start a new type of phone? Is this true or if not - what's going on with the iPhones?

I haven't heard of your theory, nothing has shown up on macrumours.com, I certainly hope not though! I think what they want to do is create a cheaper iPhone made of lower quality materials all while keeping the original higher quality series. Though who knows? I hear they have an iWatch in the works too.

Why would Apple stop making iPhones? If they're gonna make iPhones, they're gonna continue to make iPhones. The only reason why they'd stop making phones is if no one buys it or it's no longer popular and that isn't happening now is it? And if they make a new type of phone, it would still be called the iPhone (that's Apple's brand identity).

There will be an iPhone 6 but when it will come out, it will either be this year or next year (if the iPhone 5S does come out this year).

Never heard that rumor. The iPhone is their most successful product. Why would Apple stop making it for no reason?

So yes there will be an iPhone 5S, 6, 6S, etc onwards.