connecting atmega 328 with a smartphone using otg cable (on the go cable)

Well, Today I got the idea of connecting an atmega 328 microcontroller to a smartphone using an otg cable.I feel that arduino should build an app of these things.Instead of using a laptop or pc we can just connect a microcontroller to a smartphone and just start programing .We generally carry phone in our pocket well its just the matter of our convinence.I tried this first by typing a program in my laptop and then i copied that on to my usb drive and connected the usb to the otg cable on to my moto x . I used es file explorer to open it as text but unfortunately i could not upload it.i needed to pair the microcontroller to my phone which i could not i wish that arduino should develop an application which could be downloaded directly from the store as any other normal app . the app should have an option to pair with the microcontroller

Looks like that supports a lot of the common USB Serial chips, as well as the Arduino Uno.