I often find myself in a bus/train/subway/car without a tray available or any other way of managing even a small play field. There's always games on my phone, but that lacks something compared to an IRL game.
Has anyone found good ways of adapting rulesets for situations like these? Particularly for RPG(ish) games: even simpler ones seem to require more of a layout and tracking tokens etc than can be managed in situations like this. I'm by myself, but I'm not sure that matters here: anything that could be adapted in a a multiplayer game should be doable in a solo game too.
I'm interested in general techniques people have adapted themselves but I'm also new to the BG scene so I don't really know if this is a (relatively) common thing. If so, it would be useful to know of any "official" rulesets that have adaptations like this to see examples of how game designers themselves make gameplay mechanism X is mapped to table-less mechanism Y, which I could then bring with me to other games.
An example technique would be something like "pen & paper w/ pocket notebook to track token states or die rolls that would normally stay on the table". Or a type of rule that could be dropped out altogether, or dropped & replaced with a simpler mechanism. It would be really useful to have a technique for adapting a play field tiled with cards into keeping them in-hand.
EDIT: I'll leave this open a little longer, I'm not sure how to choose "the" answer though to mark it as such and close it out-- each answer is giving useful information (so thank you for that). Having the option to mark multiple answers correct when they were correct in different ways would be useful.