Tips in Dubai

Dear expats,

I just arrived to Dubai and I have a curious question regarding how tips work here...
As I noticed for example in France that they don't give tips in general, in Spain they give it, in Morocco if you don't give it they consider you are mean, in Mexico you must give at least 10% or they will blame you, in US it's mandatory and they put it in the bill as service....
So I need to know what is it like here in Dubai? Mandatory? Optional? Depends on the kind of the place we are? Is there a minimum or a percentage?

Thanks for sharing your experience regarding this topic.

Regards,
Walid.