For discretionary trading I prefer CMC Market’s brand new HTML5 trading platform, it’s sophisticated and chic. For automated trading I would go for MT5/MQL5. MQL5 is more difficult to learn than MQL4 (OOP etc.), though, that – together with old habits and comfort – is the main reason why so many still stick with MQL4. But MQL5 is more powerful and still being enhanced with cool new features. Moreover, MetaQuotes recently announced that no new MT4 licences will be granted and no new servers allotted to already existing MT4 brokers. So MT4 will finally die out and there’s no point in taking the trouble to learn a deprecated software from scratch. And cTrader is neither as powerful as MQL5 nor as cool as CMC’s platform and resources/support are very limited, plus it’s restricted to Windows.