I would like to ask what is the best firmware option for an Antminer T15!
I am not aware of any "trusted" custom firmware made for the T15, those gears are unicorns and I suppose no dev would waste their time on it, so whatever you find is probably a hack of the stock firmware or a waste of time.
(if it is possible to be able to move the machine when I am away (such as on the mobile phone per application))
What does that mean? what are you trying to achieve?