A crypto exchange. I have been using Binance since last year. Binance was created to only trade crypto currencies. In August, 2018 Binance launched the Binance Coin (BNB). In January, 2019 added the ability to purchase Bitcoin with debit and credit cards, including Visa and Mastercard.
Those of you who have had problems with other exchanges may want to give Binance a shot.
I am testing wallets and processes to see if Binance coin (BNB) would be a good crypto to add. Ethereum, Litecoin, Monero or Cardano might be good to add. Let me know if any of you have any ideas.