Hello everyone,
I've already asked this question on reddit but didn't get an answer. So maybe someone here is able to give me one
The original question:
I'm hodling a bunch of Altcoins. Some of them doesn't have an Electrum wallet which is my wallet of choice whenever it's possible (don't have to download the whole blockchain, open source and multiplatform support). My idea now is to use my old Galaxy Nexus Android device with the latest possible Lineage OS / Cyanogenmod without any additional apps (no PlayStore / Google services etc.) besides Coinomi installed. I would export the Private Keys to a LUKS encrypted USB Stick as a backup and would remain the Android device turned off and offline as long as I don't want to use the wallets.
Is this a setup which can be considered as "secure as possible"? I understand that a hardware wallet would be safer, however the hardware wallets doesn't support all of the Altcoins I'm hodling and using the desktop wallets isn't an alternative to me because of the disk space and bandwidth which is needed in order to keep syncing them.
Thanks in advance.