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The problem is that even if you go through a secure network connection (SSL or TSL), you can still be using a insecure WiFi connection. If I was a black hat kind of guy, I would set up an open WiFi in the same area as a coffee shop or some other place that traditionally has free WiFi and sit back and sip my espresso while I intercept your data. The way Safari warns you about the insecure WiFi connection, you only get a single security certificate warning for THAT connection. So if you come to the same coffee shop in the morning and afternoon, you will be warned in the morning, but I would have a good chance of snagging you in the afternoon if you weren't paying attention. Sorry to tell you this, but as far as I know, you can't adjust the settings in IOS or Safari to warn you each time. I would set a mental red flag every place I saw a WiFi with a name like "Free WiFi" and avoid it like the plague unless I was absolutely certain it was legit. Even then, I would avoid it like the common cold, but I'm a little paranoid.