Buying bitcoin is still a cumbersome process, as Quartz’s guide to investing in cryptocurrencies will attest. A new app called Dust aims to change that by automatically investing your spare change in bitcoin, litecoin, or ethereum.

Here’s how Dust works: It connects to your bank account to see your transactions. Then it rounds up each transaction to the nearest dollar—basically, collecting spare change. Once about $10 of change has been accumulated, the amount is used to buy bitcoin, litecoin, or ethereum, in proportions set by the user. The app only reads your bank’s transaction data; it doesn’t have access to the fiat or crypto funds. The cryptocurrencies are acquired through Coinbase, one of the biggest firms in the business.

Dust will work with over 9,000 financial institutions in the US, including banks like Wells Fargo, Chase, and Citi because it uses data from a service called Plaid. Plaid acts as a bridge between banks and developers who want to build apps on top of transaction and other data. The mobile payments app Venmo, for instance, also uses Plaid. The app will also work for customers of Monzo, among the buzziest of a crop of new, digital-only, British banks.

The idea of using an app to digitally gather up loose change and invest it isn’t new. The startup Acorns does this for some 850,000 customers in the US. The concept is powerful because it removes the need to think—or worry—about the right time to pull the trigger on an investment. It’s especially useful for volatile cryptocurrencies, where prices can swing 100% in a week. “It’s the same thing I recommend to my dad,” says Jordan Fish, one of Dust’s five co-founders. “It will automate [the buying decision] for people who want to get into bitcoin but never know when to buy.”

Dust is currently being tested with about 1,000 users, Fish says, with another 20,000 on the waiting list. Those thousands of users won’t have long more to wait because the Dust team will start ramping up its userbase next month, Fish says. Dust has been slow out of the gates—another app that does the same function is CoinFlash, for people with US bank accounts.

How does the project make money? At the moment it’s a part-time gig for Fish, who works at Monzo, and his co-founders. Fish says they have no plans to earn revenue from Dust at the moment and the founders are paying the bills themselves. “We’d rather self-fund until we prove we have a product people like and use regularly,” he says. One possible model is simply charging fees, Fish says, which is how Acorn makes money.

There’s another possible spanner in the works for Dust. Fish is worried that the product will have to be regulated by the UK Financial Conduct Authority. His team is looking into the legal status. “Finding clarity around that stops us from making something cool,” he says. “Because you don’t want to accidentally get put in prison.”