You could email the file to yourself. You can use a computer as an intermediary. Or as mentioned, File Browser (paid, 3rd party app). I am not sure that all of the 3rd party file managers can get to the phone??? Recently, someone mentioned File Browser might not be as supported as it once was????
File Browser is only on the pb. It can navigate to the sd card on the phone using the bridge function (no app on the phone other than bridge)
There's also an app for the BB phone (none needed on pb or computer) called wifi transfer. It works similarly to the wifi sharing - you use an ip address. It has a bit of an issue on the pb due to screen size and the touch screen.