Why is the emoji 2 app not working on my iphone 4?

I have just downloaded emoji 2 on my iphone 4 but the new emoticons are not showing up in my keyboard.
When i go to international-add keyboard.emoji isn't there as an option. I've tried deleting and readding the emoji keyboard I already had in settings, I've restarted my phone twice and I've tried both the japanese keyboards. Any suggestions?

  • Which emoji app is the original one? Which is the one that appears on the keyboard on WhatsApp (yes, I've seen it)? It's the original one, but I can't find it in the App Store. Can anyone send me a link? Using an iPhone 5, if it helps.
  • Which emoji app has the most emojis? I don't care if you have to pay or not I would just like to know which one offers you the most emoticons and which app is worth it besides the built in iPhone emoji keyboard. So what's the best one?
  • What's the best emoji icons app for iphone? There's alot of them & before I downloaded one & I just wanted to know which one is your favorite?
  • What is the emoji app called? I keep seeing everyone using these emojis that aren't on your regular keyboard on iphones, so where are they from? The best way i can describe what i'm talking about is the emojis that are just simple black and white symbols.instead of colorful hearts like the normal emojis have, this app just has a white heart that's outlined in black. Or a smiley face that's just a outlined smiley face nothing detailed like regular emojis… Anyone know what i'm talking about?