ESSSquareProgressIndicator
April 15, 2015 • Custom License
A rectangular (square), indeterminate progress indicator for iOS and OS X
MWKProgressIndicator
April 03, 2014 • MIT License
A minimal progress indicator for iOS with status update support. Displays above UINavigationBar and below the Status Bar
Circular Progress Indicator
March 30, 2013 • Public Domain License
Just a custom (determinate) Circular Progress Indicator