Soo, we see our fair share of issues with ridesharing apps coming through to support - which we’re always delighted to help with 
The most common one, which is definitely the case with Uber in the US, and I believe the same with Lyft too, is that they charge your card at the start of the ride. This tends not to make a difference, but if you split the fare with someone else, it can sometimes cause a bit of confusion. It also means that a few days after the ride, when the charge ‘finalises’ from the merchant’s side, you may see the amount, increase or reduce.
However, most customers are able to use ride sharing abroad, without issue, all while getting our fantastic exchange rates 