Is there an iPhone app that can allow me to text an international number for free?

I know there are a lot of free texting/SMS/messaging apps out there for iPhones, but my problem is texting internationally for free.

I live in the US and have unlimited 4G and SMS, so IIm willing to use my own 4G to use the app.

However, my girlfriend lives in the UK currently (in England) and her 4G is extremely limited every month. So, I d rather her be able to use regular SMS to "text" me on this app.

Essentially, I want an SMS app that works like any other decent messaging app on 4G/wi-fi for me, but gives me a UK/England cellphone number or something so we can message throughout the day.

I just want to be able to talk to her without waiting for her to get home or worrying about whether she ll have wi-fi wherever she is. And for free on her part!

Any iPhone apps (that are tried and true) and alternate suggestions are welcome!

Added (1). I should clarify that I basically want my girlfriend to be able to use JUST her cellular service and not have to pay extra to text me back on her SMS. So if there's an app where I can get a UK phone number, that'd be awesome!

Little boxes with hex code in it. How to fix?

Some webpages now show buttons only as boxes with hex code in it. What happened? How to fix this?

Added (1). It was fine some time before, then I update java and let java uninstall old versions.
It happens on many webpages now, other webpages have different wrong depictions.

Added (2). All these icons are buttons, working just fine, when clicking or hovering on it.
These pages use javascript, but I can't find how they get the image.

Added (3). I'm just the user of these sites.
The example is from
http://www.techsupportalert.com/best-free-iphone-apps.htm
No idea, how they look in real.

Added (4). I also startet my browsers (IE and firefox) in no-add-on mode.same result for the buttons.

Added (5). Thanks, Spac3nerd brought sparked the right direction. Little boxes with hex code in it. How to fix - 1

How to short stocks in thinkorswim papermoney?

I downloaded the stock simulator but can't seem to figure out a way to short stocks through there. I even downloaded the app to my iPhone and the same thing goes for that one. I want to get in the practice for when I turn 18 I already know what to expect so please help achieve this skill.

Can I activate my iPhone 5c?

So my friend has Verizon and has an iPhone 5, but he used to have a white 16GB iPhone 5c. Since he doesn't use his iPhone 5c he gave it to me. Although he has Verizon, his sim card is now inside his iPhone 5. So that makes my iPhone 5c "unlocked" correct? Anyways my actual question I guess is will AT&T activate the iPhone 5c for me if I go into my local store. I ask because I had an iPhone 5s but it broke so I had to downgrade to an iPhone 4 because that's what we had lying around at home but the store activated it for free, but both phones had only ever been with AT&T.

IPhone 4 not connecting to Wi-Fi?

My iPhone 4 has been acting up lately and it is getting rather annoying. On my settings page, it shows that I'm connected to Wi-Fi with the blue checkmark, but on the service bar on top, it shows that I'm on 3G. My phone isn't allowing me to get on any app that requires internet, and kicks me out.

**I have rebooted my phone multiple times and I still have yet to have access to the internet.

Why does this happen with the iPhone?

So sometimes (rarely, but enough to make me question it) when my boyfriend texts me it comes from his iCloud email. I told him and he told me he also experienced that sometimes when I text him, saying it comes from my email. We don't know how or why. So why does this happen?

Added (1). we both have iPhones

Iphone liquid contact indicator not red?

About two hours ago I dropped my phone into a sink full of water. I immediately turned it off, dried it and put it in a warm place to dry out.

I have also done some googling and I have been told that there's an indicator that will turn red if it comes into contact with water in the slot where I put my sim card. After opening the slot and having a good look it still appears to be silver/white. Is my phone safe?