The Good
This is by far the best app for splitting receipts. It's mainly designed for splitting receipts out at a restaurant/bar, but works equally as well for splitting things like grocery receipts.
You start by taking a picture of the receipt and it does a decent job of auto-recognizing all the items on the receipt. Then you start adding people and assigning items on the receipt to which people had them. If two people shared an item, you can tag both people on that item, and it splits it between everyone who shared that item.
After you've categorized all the items on the receipt, you can enter how much you want to tip, and it will also split the tip proportionally based on how much everyone's share of the bill was! At the end, you get a nice list of each person and how much they owe.
The app has nothing to do with actually transferring money between people, so you're expected to either have everyone throw the right amount of cash on the table, or have everyone send money electronically to the one person who pays the bill. It's great because it is specifically designed to just split the receipt, so it's super optimized for just that task.
The Not-So-Good
Don't expect to be able to get back to any past receipts in this app, it's not for recording a history of things, it's really more an in-the-moment kind of app.
The app does have a way to have other people join a bill to split a bill live instead of scanning a receipt, but I am much less impressed with that feature. It seems to be a bit complicated to join a receipt and is then more limited in how you can use it while in that mode.