cop-out answer: whatever you are most comfortable in OR whatever you most want to learn to get comfortable in. long answer: depends on the question. if you mea

cop-out answer: whatever you are most comfortable in OR whatever you most want to learn to get comfortable in. long answer: depends on the question. if you mean you as in the Royal You, hard to say, hence cop-out answer if you mean you as in me personally, then I would say it further depends. Windows desktop app? Visual Basic 6 with forms designer. Linux desktop app? I've never done it but have standing plans to find a not-terrible IDE and learn QML. Android/IOS mobile app? Xamarin Forms with .net core web app? SAFE template with .net core