How to get a text sent to me everytime someone tweets?

My friend has an iPhone and she has got this thing where whenever someone tweets (she has submitted the people she wants to get alerts from) she gets a text. I really want to get that but don't know how? I have a Blackberry Curve 8520. If you can't do it on blackberrys, I have an iPod Touch, could it send you an email or imessage?

What i have to do with my iphone?

I have an iphone 5 and this 2 days the message doesn't have sound. But when someone calls me it has. Only message sound is off, i don't know why.

Added (1). Switch on the upper left side is turn on.

Added (2). Yes it doesn't show red. And the volume buttons is up but it still doesn't.

How to modify my audio so that I can finally listen to it?

I have recorded a music performance with the iphone's voice memos but when I listened back to it there were a lot of thumps due to the bass and amps (i'm not a music genius so sorry if i'm wrong haha)… Is there any apps or any ways to modify the audio to take out that bit so I can listen to it?

I have an app idea for the iPhone?

I've had an idea for an app that lets users keep track of their money so like they put in their monthly income and track what's they are spending on bills, shopping and extras, ETC. I wasn't sure if this was a good idea or not, just looking for some advice on possibly how to improve the idea if it is good or find out if its not. Thanks and i will be developing the app myself not outsourcing it.

What would you suggest for me?

I have a PS3, Xbox360, Nintendo Wiiu, Nintendo 3DS, Android and iPhone. I play games all day, from waking up to sleep, entire day. I'm 15 years old. What would you suggest for me?

How to erase iphone contacts?

After transferring sim card to new iphone, I need to erase previous contacts from phone, all in one go.
I have too many to erase one at a time… I went to ''Erase all content and settings'' TWICE!
But iphone has NOT erased phone contacts from agenda, Help!

How to put my iphone 5 on roaming?

I'm on EE, I'm from the uk and going to Italy for a week. How do I insure my phone works and I get signal over there? Do I need to put it on roaming, if so, how?

Why won't my iPhone send iMessages to other iPhones?

I can use iMessage on my iphone4 with no problems at all to iPods, but not to my partners iphone4, it always defaults to SMS. Its frustrating, because we live in an area with poor mobile coverage, so if I need to message him urgently, iMessage in theory should be the best way of doing it. Does anyone know how I can alter this please?