The best bitcoin wallet out there is without chance Xapo it is the fastest bitcoin wallet in terms of transaction and it has double security check plus it has an online shop where you can exchange you bitcoin into different things like games or even money on your phone anywhere in the world.
The only good feature of Xapo I can even remotely consider to be useful is "no transaction fee" policy.
But from the other hand I think it gives people wrong idea about how the bitcoin network work.
Process of sending bitcoin is not completely free and transaction fee is integral part of bitcoin network.