Why get an iphone/smart phone?

[Matt the Smith Machine]

What are the reasons for getting an iphone/smart phone?

Here's a sumamry of my thoughts on iphones/smart phones;
- They are expensive MP3 Players / Phones
- You can go on the internet but 90% of the time it is used for tweeting or facebook (lame)
- You can download Apps that are interesting for about 1 day
- Some have a GPS, that's good if you travel a lot to unfamiliar palces

That's about it, my mates have iphones/smart phones and they don't seem to have any real appeal over my Sony Ericsson W810i.

Summary of thoughts

At the end of the day you will only use your iphone/smart phone to make calls, text, go on facebook and download apps that become boring rather sudden.
Seems a lot of money to spend to do such basic things.

Please enlighten me on why iphones/smart phones are worth the money.