Bitcoin exchange Coinbase briefly flew to the top spot on Apple's U.S. app store after the cryptocurrency skyrocketed in price Thursday.

The red hot digital currency surged to a record $19,000 on the online broker's site, before dipping 15 percent to $16,025 at about 4 a.m. ET Friday.

Coinbase was ranked the most popular app on the Apple Store on Thursday, according to data by market statistics firm App Annie. It is currently ranked second, below French publisher Ketchapp's mobile game Rush.

Its service was so overcrowded that its website went down for roughly an hour. Coinbase said the site was "experiencing record high traffic."

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Last month, 100,000 new users flooded the service, joining a day after derivatives exchange CME said it would launch bitcoin futures this year.

Some experts believe the introduction of futures contracts, which enable investors to agree to buy or sell an asset at a predetermined price at a set date, will lead to more institutional traders investing in the space.

But a number of big banks are unhappy with talk of bitcoin futures. The Futures Industry Association, a trade body that represents the derivatives industry, reportedly criticized the introduction of bitcoin futures in a letter to the U.S. Commodity Futures Trading Commission on Thursday.