If you've used Airdrop before for OS X, you'll realise how useful and easy the feature is. Unfortunately Apple has yet to expand Airdrop to iOS so sharing files between your Mac and iOS device can sometimes be a task which requires more effort and time than really needed.
Instashare is an app which lets you quickly transfer pictures and videos between your Mac and iOS device by simply dragging and dropping. You don't need the internet to do it either. It simply works over WiFi or Bluetooth. So the speeds are not limited to how quick your internet is. You can easily transfer hundreds of MB of pictures within minutes.
The app is free to download and use on both OS X and iOS. An Android and Windows version is also coming soon according to their website.