Recommendations can easily be subjective and local to one person or time. Please be specific about function and broad about timeframe so that your question, once answered objectively, is of use to the community. Consider instead posting your question at our sister site, Software Recommendations Stack Exchange.
Please have a look at How should I ask about getting a software recommendation? before posting questions using this tag.
Good places to start when looking for a particular type of software:
- Which OS X Applications do you find indispensable?
- What iPhone apps can't you live without?
- Which are the OS X Dashboard Widgets you can't live without?
Consider instead posting your question at our sister site, Software Recommendations Stack Exchange.