I have a checkbook. I don't have checks, but I use a checkbook to keep track of my checking account balance. This means keeping all of my receipts and recording them and balancing and... bleh. I'm a lazy guy, so I would keep putting it off, and it just wouldn't get done.
The app for my bank is not only designed and coded very poorly, but also lags by about two days. So I thought, why not make a checkbook app? And from there, Simbal was born. I could overload you with the details here, but instead I'll give you a link Simbal's page in the Google Play Store: