Does it make me surf the net anonymously?
No, while it uses Tor network, which is designed for anonymous surfing, this browser is intended just to circumvent censorship — to remove limits on accessing websites your government doesn't want you to know about.
If you are looking for something more secure you may want to try a VPN like PrivacyIO.
Does this contain any viruses or trojans?
There have been no modifications to any of the packages used, no adware, trojans, toolbars, etc. This is simply a tool to help people get around censorship.
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