Roaming in Europe: one app to rule them all?

After a long trip through France, Belgium and Germany, I’m exhausted by the sheer number of charging apps and RFID cards. Every network insists on its own account, and roaming via a single provider often means premium rates or limited access. I thought the EU was pushing for seamless interoperability, but my experience still feels fragmented. Does anyone actually have a reliable setup for cross-border charging? I’m tempted to carry three cards and two apps, but that defeats the purpose. How are you all handling roaming payments, and have you found a tariff that doesn’t penalise you for driving abroad? Curious to hear your practical solutions before my next summer road trip.