I survive for days, weeks, in Doha without cash. But of course it's handy to have some in your pocket, if you remember to mop up any excess before you leave. If I need cash I'll do a cash-for-cash exchange: the airport, malls and (some) metro stations have exchange places.
I think most of the airport taxis (no Uber) take cards, but best to check with the driver before you start the journey. If he doesn't take cards, the one behind him will. For other transport needs use the metro or Uber. Both take credit cards. If you wish to tip the Uber driver you can do so via the app. Apart from rounding up on cash payments, tipping isn't quite the thing it is in the US.
I don't tips hotel porters when they simply walk me to my room, but I know some might wish to. If that's the case your convenience is the driver, and you might choose to use your native currency.
I haven't come across a restaurant that's cash-only: a local Sri Lankan place I visit is so aware of the need to offer card payments they processed these through a neighbouring supermarket until they got properly set up with the banks.

It doesn't, not from May onwards. Though I suppose that depends on what you are used to, or welcome.
There again, a desert trip wouldn't be much fun without a measure of heat.


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I'll pass on that, although I noted kids were having the whale of a time with hands-on exhibitions in the National Museum. The Islamic Arts Museum is a must-see for grown ups, but it's anything but hands on.