You cannot compare any android phone with iPhone but you can compare Android Os with iOS.
So, let's us take iphone 7 with Samsung S7 Edge. I am avoiding Samsung S8 and iPhone 7+ because both are great if you don't have to sell your kidneys to buy them.
You will find camera quality much times better in Samsung S7 edge than iphone 7.
You get expandable memory option in S7 which is missing in iPhone 7 or any iPhone.
If you say iPhone 7 looks good then S7 Edge is also not much behind. The curved screen is a stellar and has 4k Super Amoled display. On the other hand, you don't even get Full hd display on iphone 7 but it's retina display does good job.
You can install Shareit on iphone and share pics on any android device. If you want to save pics on your pc, then just connect your iPhone with pc and simply copy paste. No itunes is required for transferring pics. But if you need to add any file to your iPhone, then you obviously need iTunes. All this tantrums are not required for Samsung S7 Edge or any android device.
Battery backup is also better in Samsung S7 Edge and it also has Fast charging which is a bliss.
Overall, i find Samsung S7 Edge better in every way. Yes, iPhone lovers will say it is smooth and sexy and it gives lag free experience but if you compare it with low end android devices, it is not fair. Ask any high end samsung user, they will tell you how amazing is the Samsung user experience, especially after Nougat update.
I have tried to give you maximum points to compare. Rest of our bros will also share their thoughts which will help you to decide.. cheers!