This would be a fairly large project for a beginner, not that I would not help you out, I just don't have the time to write the whole thing for you.
First suggestion: Do some research on android apps, specifically with activities, intents, and content providers for starters.
Second suggestion: Pick one of your two main ideas to begin with; text messaing app or phone dialer app, and add the other later on.
Third suggestion: If you are a beginner like from scratch, and you will not start out with a smaller project, I strongly suggest you start your project using as much existing software as possible. What I mean is don't write the text message app or the phone dialer app, yet. Make the shell of your app which will call the users existing text messaging app and existing phone dialer. Get that stuff under your belt and then begin replacing the existing ones with your own.
Fourth suggestion: Really consider a smaller project to start out with.
But I, like you, know what I want.... I will help you (without actually doing it for you...) in any way I can. There is a special place for android in my heart....