The information in this wiki hasn't been maintained for a good while. Some of the projects described have since been deprecated.
In particular, the "Ushahidi Platform v3.x" section contains information that is often misleading. Many details about this version of Platform have changed since.
This website is an extraction of the original Ushahidi wiki into a static form. Because of that, functions like logging in, commenting or searching will not work.
For TWITTER, Sign Up for a Twitter Dev Account, entering your application name, description, website, organization, etc then visit Using Twitter xAuth for information on obtaining xAuth which is not enabled by default. Note, you'll need to email api@twitter.com explaining that your mobile application requires xAuth to skip the request_token and authorize steps and jump right to the access_token step.
In Xcode, Right-Click target (ex MapATL) > Get Info > Targets tab, edit the Info.plist File to your new plist file (ex MapATL.plist)
You should now be able to deploy your white-labelled version of the app to the Simulator for testing, enjoy!