Would developing your own Bitcoin Wallet be safer than using known ones like Electrum? It would obviously be much simpler, with no GUI, worse overall security but no one could get their hands on its source code. I have enough programming experience myself to make it but I'm wondering if it even makes sense to do so.
Thank for your help!
Bitcoin wallets like Electrum are being developed as open source. More than one programmer is bug-fixing.
The software you are developing on your own may contain some bugs. Your app must pass through a good testing process.
Especially work as a team on a project like bitcoin will be more accurate.