Feature Request: Sandboxed Shell

I'm sure this is probably an obscure request, but the fact that there is a keybase wallet gives me hope. It would be nice is there was a sandboxed shell that's installed along with keybase. I say sandboxed because I'm thinking this would be more of a feature for iOS and Android and having separation between the OS so malicious attempts to injection attacks into keybase chat or filesystem would be avoided. I would love to be able to open keybase and manage files, send encrypted emails and run normal shell commands such as ssh, grep, sed, awk, vim, etc from within the keybase shell on iOS or Android.

The issue names no implementation files, tests, or entry points. Start by assessing how Keybase's iOS and Android clients isolate processes and filesystem access, then establish a scoped design and acceptance criteria for the proposed shell and its security boundaries.

Written by the indexing model from the issue text.