I've been getting the cashback for quite a while now. didn't believe it the first time as a lot of such apps lie about such stuff. But they are real.. have been using ZOTO50 also since last week or so. Awesome stuff from the developer. Good to see more of such great apps coming out of Nigeria!

ososoba:
I have been using them since last year July or so, best part is that the interface is really simple (not to mention the cashback )
The ZOTO50 campaign just started, and I've read somewhere that its for a limited time, so you should try it now if you want to.

But overall, its a great app.