I will confess that I am biased towards Apple but here is WHY I would suggest the iPhone over the Samsung.
If you get a new iPhone... first you back up your phone to your iTunes, then when you get your new phone you restore from back up. This way all your photos, apps, music, contacts, messages - everything is brought along. This is a massive time saver. Other than letting the computer do its thing while, restoring, you don't have to set up the phone at all. It will even keep the same ring tones, message tones, alarms, alerts, favourites ... EVERYTHING. If you're not very techy - this makes the transition basically seamless.
If you have purchased apps then I think this is one of the biggest reasons to stick with Apple.
If you haven't purchased apps and you only ever use free apps, then I guess if you're happy to spend more time setting up the new phone, learning the new software, entering all your contacts etc then you may prefer the Samsung. I think maybe the samsungs are cheaper? Well there are certainly lots of cheaper options within the android ecosystem.
Ultimately it's up to you and someone like 
@Consuela can sell you on the benefits of android. He is equally as biased to android as I am to apple. In the end, do what you will feel comfortable with and what phone you will enjoy using the most 
 
Hope that's helpful.