I have been using Bluetooth keyboard and mouse connected to my phone as a cheaper alternative to pc but what should I put down as what i play on

Put your platform as what you would normally: Android, iOS Windows Phone, etc Your keyboard and mouse shouldn't matter You could say in the description of the run about it - if you're submitting a run

If you intend to continue using these bluetooth keyboard and mouse combo, then I think you can just mention it alongside the other description of your run. If the devices affected your gameplay, like there are some lags or you managed to play faster, then you can highlight the keyboard and mouse. If not, then simply mentioning them is enough.