If you are in the US, I would say Uphold. I linked up my bank account and can purchase with my checking account.
Easy to buy and fee is minimum. The down side is it can take 5 to 7 days to settle. Your price is locked at time of purchase and you know exactly how much xrp you are going to get, but if you are looking to day trade I am not sure Uphold will work with the long settlement period.
Also you will want to apply to increase your limits as soon as you setup profile because you start with small limit.
Also they will store your xrp and even have a partnership to allow you to lend out your crypto and earn interest while you hold.
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