So I'm not completely comfortable with having my seeds stored on paper in my house.  I'm no more comfortable than I would be having a pile of cash stored in a drawer.  I was wondering if this would be safe, or safer?:  Take an old iPhone, disconnect it from the internet and store the seed in a password protected app on the phone?  At least if someone found it, they would have to get past 2 more security levels (the fingerprint unlock and then the password app code).  Knowing that the phone in the past has been connected to the internet, would it be safe if I turned off the wifi?  I figure once BTC passes $50,000 my paranoia will be such that I'll probably get a safe deposit box.  What do you think?  Safe?  Would it be safer than a password protected USB stick, if there is such a thing?