I have an Android phone. When it's connected only to my carrier's 3G network I imagine it's reasonably secure against eavesdropping (although not invulnerable). However, at times due to lack of reception or other reasons, I may connect to a public Wifi network and use my phone that way.
It worries me though. If I use my GMail app, or a banking app, or even something less important like Twitter, is my data being sent securely? Or is it likely that somebody else could be reading my messages sent in this manner?
If I load GMail or Twitter in a browser, I can see if the protocol in the URL is https, and if the certificates appear valid. Most browsers have a prominent icon to let you know when they are in secure mode and everything checks out. The Android apps I've seen have nothing like this, so as far as I can tell I have nothing more than blind hope that the developers have secured the traffic in their apps.
Are the Android apps I have sending my personal information over Wifi securely? How can I tell? And is there standard or feature of the OS that Google can use to enforce this? Or is it every developer for themselves?