Hi, I'm a BTC newbie.
I'd like to use my old smartphone as cold storage, download Electrum, disable WiFi and data connection "forever", use it to sign payments and send the signed transaction to my current smartphone running a watching-only instance of Electrum, through QRCode on screen => camera, which seems to me even safer than passing files between computers through a USB pendrive.
Is it doable or is it a new idea / feature request / suggestion?
Actually, at present no Electrum version is available on Google Play Store for an Android 2.2 phone. Maybe a cold storage only version _could_ be made available for older Android versions, recommending to cut any communications before generating the wallet (which generation would _not_ have to rely on old faulty java pseudo-random generators of course).
On Google Play Store there's an app called "Paper Wallet" which works on Android 2.2, BUT 1) It sends _keys_ through QRcode, not signed transactions 2) Mycelium doesn't seem to be able to scan those QRcodes (I haven't tried with Electrum yet... besides I haven't deeply tested Paper Wallet and I'm not even sure it does save a wallet or just generates one for you to write down stuff).
Thank you.
I recommend that you have a look at the cyanogen android firmware. This is available for a lot of android models and gives you a more current android os version, so you can run more of the recent apps!
http://www.cyanogenmod.org/