I have an idea for an app

[butterfliesinmytummy]

I've got an idea for an app, nothing like it seems to exist at the moment on the iphone App Store (not sure about android but will check on dh's phone). I'm fairly IT savvy, have built websites etc but no idea about apps. Is there an easy way of building apps, what do I need to know or do I call in a professional? I can imagine this might cost me a fair amount if I need a pro ..... Do apps always cover their costs?

What you will need is :

1. A mac / imac/ macbook pro
2. XCode sdk (free from the mac app store)
3. Knowledge of Objective C
4. Understanding of Swift (apples newly released replacement to Objective C)
5. Apple developer licience to test and relase ($100 / year)

3&4 are cross compatible, but ios 8 will accept both apps in either or both.

The last post is what you need if you want to develop for iPhone. For Android you need a PC, the Android SDK (free) and knowledge of Java.

Apps do not always cover their costs. Some (a tiny minority) make their developer very rich. Many make little or no money.