From within Infinit
First, open the Infinit application on your iOS device. Select the airplane icon in the red circle at the bottom of the screen. You will then be shown a list of photos and videos from your camera roll.
Select as many items as you'd like and tap the Next button that appears at the bottom of the screen after you've selected your first item. Upon tapping Next, you'll arrive on the send view. If you've given Infinit access to your contacts, you should see them listed here. Search or select a contact from the list.
You can also type an email address (read more) or phone number (read more) if your contact does not appear.
Once you've selected your recipients, tap the Send button at the bottom of the screen to start your transfer.
With the iOS 8 share extension
Infinit is not limited to your camera roll. You can also share PDFs, MP3s, and other non-standard iOS formats. From any other application, tap the share icon, then select Infinit. Your files will load to Infinit.
When they're done loading, tap 'GOT IT.' Open Infinit, which will display the send screen loaded with your selected files. Select a recipient from the list or type an email address or phone number. When you've added your recipients, tap send to begin your transfer.