In this youtube video, which I found on the interesting website www.topdocumentaryfilms.com, VICE host Shane Smith interviews Snowden and talks about what can be done to stop someone hacking your smartphone and recording everything you do, including what you say and where you go. Snowden gives some very interesting advice on the matter, along with comments on the broader matter of civil liberties.
I thought I'd add a few thoughts on the 'how not to be monitored by secret groups' topic. As I've got a computer science degree, plus professional experience, I do have some useful knowledge on the matter. Firstly, Snowden is absolutely right that if your smartphone is hacked, you'll have a very hard time discovering the fact. To be honest, if you are concerned about being snooped on, the only safe smartphone is no smartphone. Use random pay-phones if possible. Use old phones that are barely sufficient for calls and messages, as it'll be harder for snoopers to install useful eavesdropping software. These are the only safe-ish options. I've blogged before about the potential power of smartphones to hypnotise people while they sleep (which sounds outlandish but is perfectly feasible) and so I'm a big fan of minimum or no smartphone usage for anyone worried that they are being 'got at'.
When it comes to laptops, it is still very difficult to spot hacking and eavesdropping but there are ways to check if it's occurring. If you're connected to the internet via a router or switch, watch the packet activity light on the router. If it's chattering away when you've turned everything off to do with the internet, something funny is going on. Unplug the power to the laptop and work off its battery. If the battery is going down surprisingly quickly when all you're doing is typing an article, it's possible the laptop is sending information about you wirelessly while hiding that fact from your desktop status icons. (Clandestine groups may have hacked your laptop but they still need power to run their apps). Shut your laptop down when you're not using it; this shortens the time available to secret groups to hack your computer. You can also check your system logs to see if your computer was booted up when you weren't around. Turn on your firewall and turn off bluetooth, if possible. These acts don't guarantee that you won't be hacked (far from it!) but they do make it harder for anyone who's trying. Ultimately, assume that everything you put on your laptop or smartphone will be monitored. If you end up in a situation where you do need to hide information, store it in your head and pass it on verbally by whispering into someone's ear in a nightclub; that should be relatively safe. :-)
One final note. A lot of people respond to Snowden's revelations with 'I don't care if they're watching us, I've got nothing to hide!' For those people, I would say; 'you have nothing to hide from moral people but what if those people turned into Nazis or get taken over by Nazis?' The French Underground was rightly admired for their work in the Second World War. They'd have had a terrible time doing anything if France had introduced comprehensive surveillance before the War, for any reason. Snowden calls this problem 'turnkey tyranny' and he's right. For anyone not concerned about this threat, I'd check out the latest news from the U.S. Presidential elections…