IKNetworkActivityManager is a Cocoa class that simplifies work with UIApplication network activity indicator. It turns your networkActivityIndicatorVisible = YES/NO code to add/removeNetworkUser:, so you don't need to remember objects that can use network anymore. A demonstration App is available.
OpenUDID provides a cross-platform method for generating globally unique per-device identifiers. UDIDs are used for analytical or CRM purposes, such as to track how much time users spend in free apps before upgrading to the paid version, or for tracking the source of a download when advertising on an ad network.