Cleaning a phone that fell in the toilet

If phone is dropped in toilet and is covered with Najasah what's the way to purify it. The phone is expensive is removing the impurity by wet wipes or removing until Najasah can't be seen. Also so if najasah is on ones hand less then size of a dirham I.e the fluid from the private part not semen but the clear one. If the the person touches his phone does that become impure. Last question related to this if Najasah say again on phone but one can't see it, smell it or feel it, so like the one mentioned on previous question, if one was to touch that phone and then other thing would other things become impure. Also how does Najasah transfer, from one place to another.