Encryption?
This is what I'm worried about.
Please elaborate
http://www.businessinsider.com/david-cameron-encryption-back-doors-iphone-whatsapp-2015-7
I very much doubt they'd ever be able to sneak backdoors into encryption used in bitcoin. I'm no expert but im pretty sure that the algorithm (?) chosen was welll established and well researched (no backdoors).
'Super safe encryption that we (the govt) definitely don't want you using to encrypt your phone!' is obviously backdoored and not safe at all, but bitcoin and bitshares are entire infrastructure networks that rely on security. There is ample motivation for any motivated hacker to attempt to break private key cryptography, if it was broken somebody would have used it to steal satoshis stash long ago.
Even 'top secret' employees have huge incentive to disobey orders (and use the 'backdoor') to steal large sums of money. Such incentive only grows as bitcoin/bitshares increase in market cap.
Uptime is inversely proportional to the likelihood of broken encryption. As time and market cap increase, the likelihood that a backdoor exists but has not yet been used decreases.
If you mean the security of users devices for storing those keys, then certainly there is a problem - one that hardware wallet manufacturers will profit from solving.
Products like BitSIM already exist to securely sign transactions on any mobile SIM card device.
https://bitcoinmagazine.com/20054/bitsim-adds-secure-hardware-wallet-phone/