R10-R15. That's on a bill for 1 or 2 people.
Because of where I stay, there are Uber bikes everywhere! But I've often seen these guys pushing their bikes around because they've run out of fuel. They really do struggle to get by, wearing incorrectly sized helmets and unknowingly risking their lives daily.
Yes, Uber inflates prices, but the drivers seems hardly any of that. I try to tip at least R10 for the convenience and cost of petrol these days.
If it's raining, I tip more. If I order for more people, I aim around 20% of the bill.
As far as I'm concerned, if you don't tip the guy that rides 30 minutes in the rain to go and collect your food and deliver it to your door whilst you sit watching TV with the heater on, you're lazy and ignorant.