IPhone vs Galaxy S4 vs Droid MAXX?

Currently have an iPhone 5 that I'm content with yet I'm looking for something new and the 2 phones i've been looking at is the Samsung Galaxy S4 and the Motorola Droid MAXX

My main concerns with switching a new phone are battery, music player, and blue tooth functionality. I've had a Motorola Droid 4 in the past and ditched it within a week. I drive a lot and liked the fact that music from my iPod would automatically play through bluetooth when I turned on the car then stopped playing as soon as i turned the car off, which the droid didn't do. Do either of these droids behave like the iphone does regarding bluetooth streaming or am i gonna have the same problem as i did with my old droid?
I've had an iphone for almost 4 years now and am looking to potentially convince me to switch to a droid.

Do the iPhone 5 and 5s cases fit the 5c?

I want to buy a 3D case for my girlfriends iPhone 5c but the cases are only listed as "iPhone 5 case" IF i bought a iPhone 5 3D case would it fit a iPhone 5c? I'm aware the screen dimensions are the same but the 5c has a slightly more round back.

Is it ok to feel mad/sad because of this?

So I just got my Christmas gift. It is an iPhone 5C from my parents. I was very excited when I got it and gave them a huge hug. But the next day, I noticed that my sister got an iPhone 5S.Me and my sister are twins… Now I feel kinda mad/sad cuz that would mean my parents likes my sister more than me to buy a more expensive phone (with some cooler features).

Is this feeling ok to have? Or am I being ungrateful?

P.S.
My brother ( who is older than me) got an iPhone 5C as well.

My sister said she wanted a green 5C.

My dad in a computer engineer and researches electronics before buying them.

How much is 1gb of internet data?

I have a 16gb Iphone 5c on Sprint and i only got 1gb of data & internet in it. I use Wi-Fi all the time but how many hours would it take to use all the 1gb of internet? I used it for about 2 minutes already on facebook but then i noticed that i only had limited internet so i turned the Lte off and haven't used it since. So i would only need the internet so i can check facebook and maybe do some browsing on safari, thats it. So how much hours is 1gb worth using only facebook & safari, i won't be using it, only if it's a emergency.

Why is my iPhone 5c heating up so fast?

I just gt an iPhone 5c (blue) for christmas and it heats up really fast, like when I charge the phone it gets really hot but I don't know why anyone know? Any answers appreciated

What's a good iPhone spy app?

We have had some issues with a boy that's a little too old for my teenage daughter and he has been harassing her. We have changed her number but I would like to put some kind of app on her iPhone 4 that will let us See her text Messages and pictures and monitor certain apps she uses just in case he gets a hold of her number again we need to proceed With legal action so I can just pull up what happened. I would prefer something free or fairly cheap.

What should I name my iPhone? - 1

Okay so I got an iPhone for Christmas and he's gold. I was thinking about naming him Phoenix, Diego, Edward, Francisco or Leonardo. Help I CAN'T DECIDE.

Added (1). IF YOU'RE NOT ACTUALLY GONNA ANSWER THEN JUST DON'T. YES, I'M NAMING MY IPHONE