If u have no coding experience, then it will take too much. Firstly you have to learn java because java is the base for android app developement, then go for android application course. If u go for java you have to learn core java which is of 3 months course nd for android app development it will take 2 months to learn. After that, you can easily make anytype of android application from scartch. Nd for making that application, the time will depend upon the type of application. If u go for simple app then you can easily make within 1 day but for ecommerce type apps, you have to devote 1-2 months
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