Here are links to a few mobile apps I use regularly:
Written for Blackberry, Android, iPad, iPhone, and others. This application can retain snippets of web pages, type-written notes, hand-written notes, PDF files, etc. and keeps them all indexed. It's effectively a "personal Google" for the pieces of info you want to be able to find again, but don't want too have to spend time organizing. There's a free version, but the paid version for roughly $50 per year will index within PDF files, greatly enhancing the effectiveness of searching through your accumulated data, as well as increase the amount of storage you are allocated which keeps all your Evernote devices in sync with each other.
Android Agenda Widget:
Written for Android only. I replaced the giant clock on the home screen of my Android-based phone with this agenda application which simply shows me a list of my upcoming calendar items, saving me from having to open the calendar application or relying on alerts for only the next appointment.
Written for both Blackberry and Android. High quality audio player for managing and listening to audio and video podcasts.
Written for iPad only. Newsreader that asks for "thumbs up" or "thumbs down" on the articles it shows you, helping refine the automatic search it does of various content providers.