Kraken is one of the oldest Cryptocurreny exchange, it was founded in middle of 2011, own by Payword & having Jesse Powell as the Chief Executive Officer, Base in San Francisco United State.
I experience lot of trading skills while trading in this platform, they have a low transaction for 0.2%
Kraken is one of the front line exchange that provide Cryptocurrence to fait trading and make price information available.
Talking about security, the site has been once HACKED, but latter bounce back with more securable option, now armed with 2FA and with more security factors to keep the platform safe.
There are lot of margin trading and features in the platform and still updating for more, just to make sure their is sufficient Cryptocurrence for traders.
Kraken is available on mobile App which is where I trade mostly and it was a good experience with perfect background design.