Yes, you can just download and inastall one of those you mentioned. Just google Bolt or Opera for Blackberry. Most people find that the default OS6 browser is better, though. I tried Bolt for awhile, but I didn't care for it at all. I haven't heard too many people who prefer an alternate browser. A few, but not many.
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Bolt on my torch is slower than the OS 6 web kit browser, and opera is not made for our touch screens so you have to use the pad to navigate, the OS 6 browser is by far faster than bolt & opera.
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