regarding security, is it better to have my monero wallet on my phone or on my laptop ?
Depends on your phone and laptop. But all jokes aside a phone would usually be better (given it is updated, isnt from some spyware vendor etc) the reason is that a phone does not have root/sudo/admin rights.
But even this ain’t a super clear answer cuz it also depends on your usage. If you never touch the computer and keep it up to date and do all internet browsing on your phone it probably is more secure to keep it on your computer instead.
Anyway get a hardware wallet