But, how can one make sure that expenses are recorded in personal ledgers immediately when they happen or at the end of that day but... (see next)
...the friends/family that actually paid have different timelines for entering the expense specifics in Splitwise (or another expense-sharing app)?
When you are physically present during the purchase, use your consciousness. Make a mental note/piece of paper/mobile phone to record the expense While in checkout lane/in the break you get during transportation back to next destination, transfer the amount digitally and record the payment in Splitwise.
Yes! Until now, you might have been using Splitwise as a 'settlement' enabler but how about using it in this new 'prepayment' enabler model? Note that, this doesn't change how you pay, only when you pay to get your finances right (by the time of expense occurrence)
If you are not physically present during purchase (or pay your part of a shared bill handled by friends/family), use previous payment records and pay the maximum you expect it to cost you. You can adjust this amount down over time, if you are continuously seeing bigger refunds (What? you enjoy refunds?) or even up.
Are you specific on paying your part of taxes too? Someone is not living in Pennsylvania. Make it simple for yourself by expecting to pay/carry-over minor amounts at the end. Over time, you can manage this well too.
Does it seem tough at the first sight? I hols that the conviction to adopt financial discipline necessitates this. This is similar to tracking your food intake, workouts etc. More on those in future posts
So, in short --
Pay early. Make everyone happy. (Remember, "everyone" always includes "you")