Okay, maybe that a bold statement to say this is worth replacing tithing at your church. I by no means want you to encourage you to do that. But The RoundUp App shares the same concept as tithing and has a social purpose to it as well.
The app was created by a student at Wheaton College, in hopes of helping people begin donating to causes more consistently, on a monthly basis. And here is how to works. 
Every time you make a purchase with you credit or debit card, assuming it is an uneven number, the app will round to the closest dollar and set that money aside. At the end of every month or once you have hit your threshold, the money that has been set aside is donated to the organization you have chosen. There are only 6 organizations that RoundUp is linked with as of right now, but they are a wide variety of causes. Due to the age of the business, it is still in the growth phase and in due time, more organizations will be added.
So while I do not truly recommend you replace your tithing with this app, it is certainly a fantastic and mindless way to help do some good for our world.
This is cool! I have seen people use a similar model, but for investing in stock. I like that they are taking the same principle but helping people give. I think sometimes when people aren’t sure how much money they should give, or what 10% of their income actually is they freeze and then don’t end up tithing at all. Its great that they are taking the stress out of this for people.
I have heard of this app before and it sounds like a great, easy, simple way to donate to charities. It is a lot easier to donate less than a dollar at a time a few times a day rather than a lumpsum once a month. This could be a good way for churches to collect their tithes.