How to implement single IAP to unlock full version

I’m making a musical trainer game.

I’m planning to release it free, with a single IAP option to remove the iAd banner and simultaneously unlock full gameplay.

Would it be appropriate to use Soom-La (http://soom.la) to do this?

Can anyone link me to a step by step tutorial on how to do this (Soom-La or otherwise)?

I’m looking for a “hello world” of IAP from Unity on an iOS device, where there is just one single thing to be purchased.

I have gone into iTunes connect, created a new app and gone into IAP and created a single item priced at $1. But how to move forwards?

(The Soom-La download appears to be a fully functional virtual store, which is overkill for my situation. Also I’m not sure if they are using their own store. And if they are, then doesn’t Apple forbid their parties allowing money transactions? There are too many things I don’t know… )

Also askied here: http://forum.unity3d.com/threads/228735-How-to-implement-single-IAP-to-unlock-full-version-of-game

For what you’re trying to do you should use the SOOMLA open framework: http://project.soom.la

This is an open source SDK for defining in app purchases in free to play games, without the full fledged store. Specifically have a look at the Unity3d project in Github - it has docs and examples which should help you.