My iPhone home button is not working?

Last night, while I was using the YouTube app on my iPhone 4, it suddenly froze, but eventually unfroze and I just double pressed the home button to switch to another app I was using. When I tried switching back to the YouTube app by double tapping the home button again, it did not work. So I pressed it once and it didn't bring me to the home screen. Several hours later and I'm still stuck on the Kik app. I tried holding the power button so I can swipe the screen to turn off my phone, but it didn't even pop up. And I know the home button isn't broken because when I turn off my phone (not the power, just clicking it off) and press the home button, it turns back on. But oddly, it doesn't even ask for my passcode or anything, it just goes straight to the Kik app I was on.

Does anyone know what the hell is going on?

Why does this keep happening?

I have a Samsung galaxy note 3 and my girlfriend has a iPhone 4s, I notice when she texts me long paragraphs, I don't get it in order as they should be read, I get it all mixed up, also whenever I send her an emoji, it comes up as a question mark

Upgrading iPhone 4s to 5s or wait for 6?

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The only reason I want to upgrade is cause the Wi-Fi of my 4S is acting really weird and hasn't been working for the past 2 months. But if it weren't for the Wi-Fi breaking, my 4S would still be perfect for me. So my question is should I sell it now and buy a 2nd hand 5S or sell it when the 6 comes out? What features will the 6 have over the 5S? I'm really scared that the 6 will have a huge *** screen like Androids which I'm definitely not a fan of.

Sleeping with an iPhone under my pillow?

I have heard that sleeping with a phone underneath your pillow can cause brain cancer because of the radiation. I have done this for 2 years and I'm a bit worried because younger people are more vulnerable and I'm still under 18. Will this have caused much damage? If I stop now will everything be ok?

How to switch off data roaming on iphone 4s?

I'm trying to avoid any additional charges when i go abroad but can't see how to switch off data roaming.
I have iphone 4s. I have looked on line and it says to go to general, then network but i don't have a net work button.
In general i have;
About, software update, siri, spotlight search, text size, accessiblity, usage, background app refresh,
auto lock, restrictions, date & time, keyboard, international, itunes Wi-Fi sync, VPN, reset.

I have been into all of them and can't see data roaming button.

Can anyone help please?

Is the OnePlus One worth it?

Currently I have the iPhone 4, second-hand, and the earpiece doesn't work, so I can't make calls. It was was my grandma's phone, but she gave it to me as a gift. There's no SIM card in it, so I use it as an iPod. I have a third-hand (is that a thing?) Orange San Francisco. It is about 4 years old and runs off Android 2.0.1. It can't be updated anymore. It has a 3.5" 420p screen and my iPhone has a 3.7" 720p.

So, because I'm 15 now, and I have never had a new, first-hand mobile, my parents said I could get a brand new high-end smartphone. They also said they would put forward £100 towards it. I originally wanted the HTC One M8, but then I saw the price. I then opted down to a HTC One Mini 2 (HTC One M8 Mini), but then discovered the Nexus 5. A budget phone with top end specs, I thought it was perfect. £299 for a 16GB phone with a 5" screen.

I have constantly seen my friends get new phones, (one of them gets a new phone every 6 months, and currently has an iPhone 5s and a HTC One M8!)

It was settled. I was going to get the Nexus 5. Then my friend told me about the OnePlus One. For £269, I could get a 64GB model with a 5.5" 1080p screen. 3GB of RAM, Adreno 330, Snapdragon 801 and Cynogenmod 11s.

So I want to make sure this is a legit phone, and I heard you need an "invite" to get a copy of the phone currently.
Will this be publicly released?
If so, will there be any good Pay As You Go deals in the UK?