Shared bills

My sister and I are on our 5th trip using the Splitwise app. I find it very easy to use. There is a pro version with a few more features but I do fine with the free version.

I've also used Splitwise and found it handy especially since you can enter the local currency and it sorts out the conversion for you, plus you can enter % split or actual amounts. But know that the free version caps the number of transactions per day (it's either 3 or 5 I can't recall). With a group of that size you might want to rotate through payers each day so more than one person logs expenses for the day or just spring for the pro version (it's not that expensive).

My sister and I use the Tricount app. It’s easy to use and seems accurate.

I used the Splid app for a trip like that recently. I had researched the best app that was free and also would do multi currency. I kept track of all. Friends shared receipts with me as we took turns paying for things and I logged the expenses. But I think I could have shared the app and they could have loaded their own expenses. We agreed to just share equally. Not sure if you could do more individually like who had the burger and who had the filet mignon.

I like Splitwise and it has always worked well for me.

Why not go ‘old school’ and pay cash for your meals? I travel with my two siblings and we find this system works very well.

If you all have Venmo it has a feature where you create the group and then the app calculates it for you. Because I have so many dietary restrictions I often am frustrated if groceries or meals are combined and with Venmo whoever paid the bill would enter only the names of those who "partook". It's especially good if you have some big drinkers and some who don't!
For a group museum admission, I paid, and entered everyone's name except one who had an online pass. Your balance owed goes up or down as you "host".