It would be so handy if we could setup automated buying and selling of bitcoins, stocks and shares. For example, when the value of bitcoins falls below a defined amount and the recent performance looks good, buy bitcoins using £X. When I’m running low on funds in my Monzo account and predicting something expensive very soon (insurance renewal, hotel room charge, etc) then automatically sell and withdraw. Could also use it to automatically buy Monzo shares 
I’d also like to have a dedicated virtual savings pot for making automated purchases such as these.
I know services/apps exist with alerts for when a stock or currency goes above or below a designated amount, but none with the automated purchase feature and with the exception of Coinbase I’ve not found any that are nice to use. Even that doesn’t yet allow me to buy with Monzo due to lack of 3DSecure, nor does it support anything other than Bitcoin or Ethereum.
I may be wanting one feature to do too much things so maybe worth splitting them off, however as it’s all related to automated buying/selling of investments it does kind of make sense to include in one topic.