1. It doesn't accept my email address. Looks like the pattern is way too strict and doesn't allow any new TLDs.
2. The use-case I most often see Splitwise used for is trips abroad with friends. In this situation, expenses are often recorded while no internet connection is available and synced later. I'm not sure if IOU supports this, I haven't tried it.
So far I have two issues with your solution:
1. It doesn't accept my email address. Looks like the pattern is way too strict and doesn't allow any new TLDs.
2. The use-case I most often see Splitwise used for is trips abroad with friends. In this situation, expenses are often recorded while no internet connection is available and synced later. I'm not sure if IOU supports this, I haven't tried it.