Re: Using old smartphone as cold storage, signed transaction => QRcode
Sure, with the 24 word seed you can recover your private keys without using the trezor. I had to do this lately to transfer some coins which I bought in an ICO. 
I see, thank you. I might buy a Trezor (not available in this country), besides trying the cyanogenmod thing on my LG P500 one of these days.
I would be careful with using an old smartphone. Their hardware may fail at any time or your OS may get stuck in a bootloop. Atleast make sure you have proper back-ups of the wallet.
I guess your idea would work well though. The scans are very easy to use then. I think it would be best to do a full hard reset of the phone data, download the app and then go offline for ever.
I guess your idea would work well though. The scans are very easy to use then. I think it would be best to do a full hard reset of the phone data, download the app and then go offline for ever.
Thank you, I do have a more recent smartphone, the idea was to use the old one - keeping it offline - just as a cold storage (*) and the more recent one as the watch-only part, and have the two communicate through QRcode/camera.
(*) I might also keep as a "colder" storage the wallet I generated after booting - ethernet cable unplugged - a live DVD Linux distro coming with Electrum, and transfer to the wallet I'd also have on the old smarphone just what I think I might need to spend while away from my PC.