ZimpleMoney is described as 'takes the time, frustration and poor memory out of family and friend loans and intra family loans'. There are five alternatives to ZimpleMoney, not only websites but also apps for a variety of platforms, including Android, iPhone, iPad and Blackberry. The best alternative is Venmo. It's not free, so if you're looking for a free alternative, you could try MoneyMailMe or LendPal. Other great sites and apps similar to ZimpleMoney are Exilend (Free) and Ledge (Freemium).
LendPal is the easy way keep track of money and other items you borrow or lend to friends, family or roommates. Splitting the rent, managing your home expenses, sharing groceries or keeping track of your balances with roommates, family and friends.
Exilend is Friends & Family Lending platform which brings lenders and borrowers together and help create & track loans, provides payment reminders, extensive reports and many features. Available for free on Web & Android!