Doesnt matter one single bit so long as the wallet you using has support for your private key. You simply import your private key into said wallet app and then you have access to your wallet and BTC funds. I suggest only using wallets where you own the private key because otherwise your coins are not actually yours. This is why you hear people say not to leave coins in an exchanges wallet for too long.
Thanks Mr. Mike.
Yes, my BTC are (or are managed) in my desktop Electrum wallet, so I have my own private keys.
What I understand here is that, instead of transferring (sending) coins in my phone wallet app, I just need to import my private key(s).
Is this an advantage vs sending the coins?