How did we do it before phones? Instant online payment is nice but rarely a requirement. Most times we split a bill with friends in a restaurant we agree on paying someone but although we technically could we don't all grab our phone at the exact moment, preferring enjoying the real social conversations we have. We tend to pay them later, and that later is more often than not at home and when I do a swift transfer to someone I'd rather have my complete laptop screen anyway to verify the banking data.

As for Uber and messaging, you are moving the goalpost.

uber still worked from the webpage last time I checked.

There are messaging apps available on linux.