What you pay is three numbers
Menu price, delivery fee, and service fee. Apps differ mostly on the second and third, and on how transparently they show them.
Zuma shows all three before you confirm. So does Glovo. Compare the total, not the delivery fee.
Restaurant commission is why menu prices differ
Delivery apps typically charge restaurants 20-30% commission. Many restaurants raise their delivery menu prices to absorb it, so the same dish costs more in-app than in the restaurant.
This is normal and not dishonest, but it means comparing menu prices across apps tells you about commission rates, not about the restaurant.
Why food arrives cold
Almost always because the rider was dispatched before the kitchen started cooking, or batched with another order that added a detour.
Zuma pre-dispatches riders to arrive at the estimated ready time and only batches orders where it does not delay the food. That is a policy choice, not a technology advantage — any app could do it.
Coverage
Glovo is strong in Kenya, Ghana, Nigeria, Uganda and Morocco. Chowdeck has grown quickly in Nigeria. Zuma Food operates in its 21 live markets. In practice, use whichever has your favourite restaurant.