If you’re looking to share with someone on the same wireless network, search the Play store for a secure wifi file transfer app. Most of them work by turning the device into a mini server, which anyone else on the wifi network can access via their browser through a temporary IP address you give them (most let you set up a password, too).
Airdroid is an easier choice for less technical people. They had some serious security issues, but I think they’ve now been resolved.
